TY - JOUR A1 - Sperlich, Paula F. A1 - Holmberg, Hans-Christer A1 - Reed, Jennifer L. A1 - Zinner, Christoph A1 - Mester, Joachim A1 - Sperlich, Billy T1 - Individual versus standardized running protocols in the determination of VO\(_{2max}\) JF - Journal of Sports Science and Medicine N2 - The purpose of this study was to determine whether an individually designed incremental exercise protocol results in greater rates of oxygen uptake VO\(_{2max}\) than standardized testing. Fourteen well-trained, male runners performed five incremental protocols in randomized order to measure their VO\(_{2max}\): i) an incremental test (INC\(_{S+I}\)) with pre-defined increases in speed (2 min at 8.64 km.h\(^{-1}\), then a rise of 1.44 km.h\(^{-1}\) every 30 s up to 14.4 km.h\(^{-1}\)) and thereafter inclination (0.5.every 30 s); ii) an incremental test (INC\(_{I}\)) at constant speed (14.4 km.h\(^{-1}\)) and increasing inclination (2 degrees every 2 min from the initial 0 degrees); iii) an incremental test (INC\(_{S}\)) at constant inclination (0 degrees) and increasing speed (0.5 km.h\(^{-1}\) every 30 s from the initial 12.0 km.h\(^{-1}\)); iv) a graded exercise protocol (GXP) at a 1 degrees incline with increasing speed (initially 8.64 km.h\(^{-1}\) + 1.44 km.h\(^{-1}\) every 5 min); v) an individual exercise protocol (INDXP) in which the runner chose the inclination and speed. VO\(_{2max}\) was lowest (-4.2%) during the GXP (p = 0.01; d = 0.06 - 0.61) compared to all other tests. The highest rating of perceived exertion, heart rate, ventilation and end-exercise blood lactate concentration were similar between the different protocols (p < 0.05). The time to exhaustion ranged from 7 min 18 sec (INC\(_{S}\)) to 25 min 30 sec (GXP) (p = 0.01). The VO\(_{2max}\) attained by employing an individual treadmill protocol does not differ from the values derived from various standardized incremental protocols. KW - maximum oxygen uptake KW - aerobic power KW - treadmill running KW - ramp test KW - treadmill protocol Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-151890 VL - 14 ER - TY - JOUR A1 - Sperlich, Billy A1 - Wallmann-Sperlich, Birgit A1 - Zinner, Christoph A1 - Von Stauffenberg, Valerie A1 - Losert, Helena A1 - Holmberg, Hans-Christer T1 - Functional High-intensity Circuit Training Improves Body Composition,Peak Oxygen Uptake, Strength, and Alters Certain Dimensions of Quality of Life in Overweight Women JF - Frontiers in Physiology N2 - The effects of circuit-like functional high-intensity training (Circuit\(_{HIIT}\)) alone or in combination with high-volume low-intensity exercise (Circuit\(_{combined}\)) on selected cardio-respiratory and metabolic parameters, body composition, functional strength and the quality of life of overweight women were compared. In this single-center, two-armed randomized, controlled study, overweight women performed 9-weeks (3 sessions·wk\(^{−1}\)) of either Circuit\(_{HIIT}\) (n = 11), or Circuit\(_{combined}\) (n = 8). Peak oxygen uptake and perception of physical pain were increased to a greater extent (p < 0.05) by Circuit\(_{HIIT}\), whereas Circuit\(_{combined}\) improved perception of general health more (p < 0.05). Both interventions lowered body mass, body-mass-index, waist-to-hip ratio, fat mass, and enhanced fat-free mass; decreased ratings of perceived exertion during submaximal treadmill running; improved the numbers of push-ups, burpees, one-legged squats, and 30-s skipping performed, as well as the height of counter-movement jumps; and improved physical and social functioning, role of physical limitations, vitality, role of emotional limitations, and mental health to a similar extent (all p < 0.05). Either forms of these multi-stimulating, circuit-like, multiple-joint training can be employed to improve body composition, selected variables of functional strength, and certain dimensions of quality of life in overweight women. However, Circuit\(_{HIIT}\) improves peak oxygen uptake to a greater extent, but with more perception of pain, whereas Circuit\(_{Combined}\) results in better perception of general health. KW - power training KW - aerobic fitness KW - body composition KW - female KW - functional training KW - interval training Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171015 VL - 8 IS - 172 ER - TY - JOUR A1 - Wallmann-Sperlich, Birgit A1 - Düking, Peter A1 - Müller, Miriam A1 - Froböse, Ingo A1 - Sperlich, Billy T1 - Type and intensity distribution of structured and incidental lifestyle physical activity of students and office workers: a retrospective content analysis JF - BMC Public Health N2 - Background Physical activity (PA) guidelines acknowledge the health benefits of regular moderate-to-vigorous physical activity (MVPA) regardless of bout duration. However, little knowledge exists concerning the type and intensity distribution of structured and incidental lifestyle PA of students and office workers. The present study aimed to i) assess the duration and distribution of intensity of MVPAs during waking hours ≥50% of heart rate reserve (HRR), ii) to identify the type of PA through diary assessment, iii) to assign these activities into structured and lifestyle incidental PA, and iv) to compare this information between students and office workers. Methods Twenty-three healthy participants (11 students, 12 office workers) recorded heart rate (HR) with a wrist-worn HR monitor (Polar M600) and filled out a PA diary throughout seven consecutive days (i.e. ≥ 8 waking h/day). Relative HR zones were calculated, and PA diary information was coded using the Compendium of PA. We matched HR data with the reported PA and identified PA bouts during waking time ≥ 50% HRR concerning duration, HRR zone, type of PA, and assigned each activity to incidental and structured PA. Descriptive measures for time spend in different HRR zones and differences between students and office workers were calculated. Results In total, we analyzed 276.894 s (76 h 54 min 54 s) of waking time in HRR zones ≥50% and identified 169 different types of PA. The participants spend 31.9 ± 27.1 min/day or 3.9 ± 3.2% of their waking time in zones of ≥50% HRR with no difference between students and office workers (p > 0.01). The proportion of assigned incidental lifestyle PA was 76.9 ± 22.5%. Conclusions The present study provides initial insights regarding the type, amount, and distribution of intensity of structured and incidental lifestyle PA ≥ 50% HRR. Findings show a substantial amount of incidental lifestyle PA during waking hours and display the importance of promoting a physically active lifestyle. Future research could employ ambulatory assessments with integrated electronic diaries to detect information on the type and context of MVPA during the day. KW - incidental lifestyle physical activity KW - vigorous intermittent lifestyle physical activities KW - physical activity KW - diary KW - structured physical activity KW - context Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301217 VL - 22 ER - TY - JOUR A1 - Düking, Peter A1 - Tafler, Marie A1 - Wallmann-Sperlich, Birgit A1 - Sperlich, Billy A1 - Kleih, Sonja T1 - Behavior Change Techniques in Wrist-Worn Wearables to Promote Physical Activity: Content Analysis JF - JMIR Mhealth and Uhealth N2 - Background: Decreasing levels of physical activity (PA) increase the incidences of noncommunicable diseases, obesity, and mortality. To counteract these developments, interventions aiming to increase PA are urgently needed. Mobile health (mHealth) solutions such as wearable sensors (wearables) may assist with an improvement in PA. Objective: The aim of this study is to examine which behavior change techniques (BCTs) are incorporated in currently available commercial high-end wearables that target users’ PA behavior. Methods: The BCTs incorporated in 5 different high-end wearables (Apple Watch Series 3, Garmin Vívoactive 3, Fitbit Versa, Xiaomi Amazfit Stratos 2, and Polar M600) were assessed by 2 researchers using the BCT Taxonomy version 1 (BCTTv1). Effectiveness of the incorporated BCTs in promoting PA behavior was assessed by a content analysis of the existing literature. Results: The most common BCTs were goal setting (behavior), action planning, review behavior goal(s), discrepancy between current behavior and goal, feedback on behavior, self-monitoring of behavior, and biofeedback. Fitbit Versa, Garmin Vívoactive 3, Apple Watch Series 3, Polar M600, and Xiaomi Amazfit Stratos 2 incorporated 17, 16, 12, 11, and 11 BCTs, respectively, which are proven to effectively promote PA. Conclusions: Wearables employ different numbers and combinations of BCTs, which might impact their effectiveness in improving PA. To promote PA by employing wearables, we encourage researchers to develop a taxonomy specifically designed to assess BCTs incorporated in wearables. We also encourage manufacturers to customize BCTs based on the targeted populations. KW - cardiorespiratory fitness KW - innovation KW - smartwatch KW - technology KW - wearable KW - eHealth KW - mHealth Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230556 VL - 8 IS - 11 ER - TY - JOUR A1 - Sperlich, Billy A1 - Becker, Martin A1 - Hotho, Andreas A1 - Wallmann-Sperlich, Birgit A1 - Sareban, Mahdi A1 - Winkert, Kay A1 - Steinacker, Jürgen M. A1 - Treff, Gunnar T1 - Sedentary behavior among national elite rowers during off-training — a pilot study JF - Frontiers in Physiology N2 - The aim of this pilot study was to analyze the off-training physical activity (PA) profile in national elite German U23 rowers during 31 days of their preparation period. The hours spent in each PA category (i.e., sedentary: <1.5 metabolic equivalents (MET); light physical activity: 1.5–3 MET; moderate physical activity: 3–6 MET and vigorous intense physical activity: >6 MET) were calculated for every valid day (i.e., >480 min of wear time). The off-training PA during 21 weekdays and 10 weekend days of the final 11-week preparation period was assessed by the wrist-worn multisensory device Microsoft Band II (MSBII). A total of 11 rowers provided valid data (i.e., >480 min/day) for 11.6 week days and 4.8 weekend days during the 31 days observation period. The average sedentary time was 11.63 ± 1.25 h per day during the week and 12.49 ± 1.10 h per day on the weekend, with a tendency to be higher on the weekend compared to weekdays (p = 0.06; d = 0.73). The average time in light, moderate and vigorous PA during the weekdays was 1.27 ± 1.15, 0.76 ± 0.37, 0.51 ± 0.44 h per day, and 0.67 ± 0.43, 0.59 ± 0.37, 0.53 ± 0.32 h per weekend day. Light physical activity was higher during weekdays compared to the weekend (p = 0.04; d = 0.69). Based on our pilot study of 11 national elite rowers we conclude that rowers display a considerable sedentary off-training behavior of more than 11.5 h/day. KW - recovery KW - sedentary behavior KW - accelerometer KW - microsoft band 2 KW - multi-sensor KW - wearable Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158753 VL - 8 IS - 655 ER - TY - JOUR A1 - Sperlich, Billy A1 - De Clerck, Ine A1 - Zinner, Christoph A1 - Holmberg,, Hans-Christer A1 - Wallmann-Sperlich, Birgit T1 - Prolonged sitting interrupted by 6-min of high-intensity exercise: circulatory, metabolic, hormonal, thermal, cognitive, and perceptual responses JF - Frontiers in Physiology N2 - The aim was to examine certain aspects of circulatory, metabolic, hormonal, thermoregulatory, cognitive, and perceptual responses while sitting following a brief session of high-intensity interval exercise. Twelve students (five men; age, 22 ± 2 years) performed two trials involving either simply sitting for 180 min (SIT) or sitting for this same period with a 6-min session of high-intensity exercise after 60 min (SIT+HIIT). At T\(_0\) (after 30 min of resting), T\(_1\) (after a 20-min breakfast), T\(_2\) (after sitting for 1 h), T\(_3\) (immediately after the HIIT), T\(_4\), T\(_5\), T\(_6\), and T\(_7\) (30, 60, 90, and 120 min after the HIIT), circulatory, metabolic, hormonal, thermoregulatory, cognitive, and perceptual responses were assessed. The blood lactate concentration (at T\(_3\)–T\(_5\)), heart rate (at T\(_3\)–T\(_6\)), oxygen uptake (at T\(_3\)–T\(_7\)), respiratory exchange ratio, and sensations of heat (T\(_3\)–T\(_5\)), sweating (T\(_3\), T\(_4\)) and odor (T\(_3\)), as well as perception of vigor (T\(_3\)–T\(_6\)), were higher and the respiratory exchange ratio (T\(_4\)–T\(_7\)) and mean body and skin temperatures (T\(_3\)) lower in the SIT+HIIT than the SIT trial. Levels of blood glucose and salivary cortisol, cerebral oxygenation, and feelings of anxiety/depression, fatigue or hostility, as well as the variables of cognitive function assessed by the Stroop test did not differ between SIT and SIT+HIIT. In conclusion, interruption of prolonged sitting with a 6-min session of HIIT induced more pronounced circulatory and metabolic responses and improved certain aspects of perception, without affecting selected hormonal, thermoregulatory or cognitive functions. KW - inactivity KW - high-intensity interval training KW - sedentary lifestyle KW - students KW - workplace KW - intervention KW - physical activity KW - health promotion Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177307 VL - 9 IS - 1279 ER - TY - JOUR A1 - Sperlich, Billy A1 - Hahn, Lea-Sofie A1 - Edel, Antonia A1 - Behr, Tino A1 - Helmprobst, Julian A1 - Leppich, Robert A1 - Wallmann-Sperlich, Birgit A1 - Holmberg, Hans-Christer T1 - A 4-week intervention involving mobile-based daily 6-minute micro-sessions of functional high-intensity circuit training improves strength and quality of life, but not cardio-respiratory fitness of young untrained adults JF - Frontiers in Physiology N2 - The present study was designed to assess the psycho-physiological responses of physically untrained individuals to mobile-based multi-stimulating, circuit-like, multiple-joint conditioning (Circuit\(_{HIIT}\)) performed either once (1xCircuitHIIT) or twice (2xCircuit\(_{HIIT}\)) daily for 4 weeks. In this single-center, two-arm randomized, controlled study, 24 men and women (age: 25 ± 5 years) first received no training instructions for 4 weeks and then performed 4 weeks of either 1xCircuitHIIT or 2xCircuit\(_{HIIT}\) (5 men and 7 women in each group) daily. The 1xCircuitHIIT and 2xCircuit\(_{HIIT}\) participants carried out 90.7 and 85.7% of all planned training sessions, respectively, with average heart rates during the 6-min sessions of 74.3 and 70.8% of maximal heart rate. Body, fat and fat-free mass, and metabolic rate at rest did not differ between the groups or between time-points of measurement. Heart rate while running at 6 km⋅h\(^{-1}\) declined after the intervention in both groups. Submaximal and peak oxygen uptake, the respiratory exchange ratio and heart rate recovery were not altered by either intervention. The maximal numbers of push-ups, leg-levers, burpees, 45°-one-legged squats and 30-s skipping, as well as perception of general health improved in both groups. Our 1xCircuit\(_{HIIT}\) or 2xCircuit\(_{HIIT}\) interventions improved certain parameters of functional strength and certain dimensions of quality of life in young untrained individuals. However, they were not sufficient to enhance cardio-respiratory fitness, in particular peak oxygen uptake. KW - aerobic fitness KW - body composition KW - functional training KW - mHealth KW - power training KW - V800 KW - wearable KW - web-based apps Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176565 VL - 9 IS - 423 ER - TY - JOUR A1 - Kilian, Yvonne A1 - Wehmeier, Udo F. A1 - Wahl, Patrick A1 - Mester, Joachim A1 - Hilberg, Thomas A1 - Sperlich, Billy T1 - Acute Response of Circulating Vascular Regulating MicroRNAs during and after High-Intensity and High-Volume Cycling in Children JF - Frontiers in Physiology N2 - Aim: The aim of the present study was to analyze the response of vascular circulating microRNAs (miRNAs; miR-16, miR-21, miR-126) and the VEGF mRNA following an acute bout of HIIT and HVT in children. Methods: Twelve healthy competitive young male cyclists (14.4 ± 0.8 years; 57.9 ± 9.4 ml•min−1•kg−1 peak oxygen uptake) performed one session of high intensity 4 × 4 min intervals (HIIT) at 90–95% peak power output (PPO), each interval separated by 3 min of active recovery, and one high volume session (HVT) consisting of a constant load exercise for 90 min at 60% PPO. Capillary blood from the earlobe was collected under resting conditions, during exercise (d1 = 20 min, d2 = 30 min, d3 = 60 min), and 0, 30, 60, 180 min after the exercise to determine miR-16, -21, -126, and VEGF mRNA. Results: HVT significantly increased miR-16 and miR-126 during and after the exercise compared to pre-values, whereas HIIT showed no significant influence on the miRNAs compared to pre-values. VEGF mRNA significantly increased during and after HIIT (d1, 30′, 60′, 180′) and HVT (d3, 0′, 60′). Conclusion: Results of the present investigation suggest a volume dependent exercise regulation of vascular regulating miRNAs (miR-16, miR-21, miR-126) in children. In line with previous data, our data show that acute exercise can alter circulating miRNAs profiles that might be used as novel biomarkers to monitor acute and chronic changes due to exercise in various tissues. KW - children KW - endurance KW - exercise KW - microRNAs KW - training adaptation Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165261 VL - 7 IS - 92 ER - TY - JOUR A1 - Born, Dennis-Peter A1 - Zinner, Christoph A1 - Düking, Peter A1 - Sperlich, Billy T1 - Multi-Directional Sprint Training Improves Change-Of-Direction Speed and Reactive Agility in Young Highly Trained Soccer Players JF - Journal of Sports Science and Medicine N2 - The aim of this study was to evaluate the effect of a repeated sprint training with multi-directional change-of-direction (COD) movements (RSmulti) compared to repeated shuttle sprints (RSS) on variables related to COD speed and reactive agility. Nineteen highly-trained male U15 soccer players were assigned into two groups performing either RSmulti or RSS. For both groups, each training session involved 20 repeated 15 s sprints interspersed with 30 s recovery. With RSmulti the COD movements were randomized and performed in response to a visual stimulus, while the RSS involved predefined 180° COD movements. Before and following the six training sessions, performance in the Illinois agility test (IAT), COD speed in response to a visual stimulus, 20 m linear sprint time and vertical jumping height were assessed. Both groups improved their performance in the IAT (p < 0.01, ES = 1.13; p = 0.01, ES = 0.55). The COD speed in response to a visual stimulus improved with the RSmulti (p < 0.01, ES = 1.03), but not the RSS (p = 0.46, ES = 0.28). No differences were found for 20 m sprint time (P=0.73, ES = 0.07; p = 0.14, ES = 0.28) or vertical jumping height (p = 0.46, ES = 0.11; p = 0.29, ES = 0.12) for the RSmulti and RSS, respectively. In conclusion, performance in the IAT improved with the RSmulti as well as RSS. With the RSmulti however, the COD movements are performed in response to a visual stimulus, which may result in specific adaptations that improve COD speed and reactive agility in young highly trained soccer players. KW - team sport KW - COD movements KW - repeated shuttle sprints KW - speed KW - Speedcourt Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146866 UR - http://www.jssm.org/researchjssm-15-314.xml.xml VL - 15 ER - TY - JOUR A1 - Zinner, Christoph A1 - Sperlich, Billy A1 - Krueger, Malte A1 - Focke, Tim A1 - Reed, Jennifer A1 - Mester, Joachim T1 - Strength, Endurance, Throwing Velocity and in-Water Jump Performance of Elite German Water Polo Players JF - Journal of Human Kinetics N2 - The purpose of this study was threefold: 1) to assess the eggbeater kick and throwing performance using a number of water polo specific tests, 2) to explore the relation between the eggbeater kick and throwing performance, and 3) to investigate the relation between the eggbeater kick in the water and strength tests performed in a controlled laboratory setting in elite water polo players. Fifteen male water polo players of the German National Team completed dynamic and isometric strength tests for muscle groups (adductor, abductor, abdominal, pectoralis) frequently used during water polo. After these laboratory strength tests, six water polo specific in-water tests were conducted. The eggbeater kick assessed leg endurance and agility, maximal throwing velocity and jump height. A 400 m test and a sprint test examined aerobic and anaerobic performance. The strongest correlation was found between jump height and arm length (p < 0.001, r = 0.89). The laboratory diagnostics of important muscles showed positive correlations with the results of the in-water tests (p < 0.05, r = 0.52-0.70). Muscular strength of the adductor, abdominal and pectoralis muscles was positively related to in-water endurance agility as assessed by the eggbeater kick (p < 0.05; r = 0.53-0.66). Findings from the current study emphasize the need to assess indices of water polo performance both in and out of the water as well as the relation among these parameters to best assess the complex profile of water polo players. KW - physiological characteristics KW - cinematographic analysis KW - penalty throw KW - strength KW - jump height KW - team sports KW - diagnostics KW - anaerobic and aerobic testing Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-148812 VL - 45 ER - TY - JOUR A1 - Zinner, Christoph A1 - Sperlich, Billy A1 - Wahl, Patrick A1 - Mester, Joachim T1 - Classification of selected cardiopulmonary variables of elite athletes of different age, gender, and disciplines during incremental exercise testing JF - SpringerPlus N2 - Incremental exercise testing is frequently used as a tool for evaluating determinants of endurance performance. The available reference values for the peak oxygen uptake \((VO_{2peak})\), % of \(VO_{2peak}\) , running speed at the lactate threshold \((v_{LT})\), running economy (RE), and maximal running speed \((v_{peak})\) for different age, gender, and disciplines are not sufficient for the elite athletic population. The key variables of 491 young athletes (age range 12–21 years; 250 males, 241 females) assessed during a running step test protocol \((2.4 m s^{−1} ; increase 0.4 m s^{−1} 5 min^{−1})\) were analysed in five subgroups, which were related to combat-, team-, endurance-, sprint- and power-, and racquet-related disciplines. Compared with female athletes, male athletes achieved a higher \(v_{peak}\) (P = 0.004). The body mass, lean body mass, height, abs. \(VO_{2peak} (ml min^{−1})\), rel. \(VO_{2peak} (ml kg^{−1} min^{−1})\), rel. \(VO_{2peak} (ml min^{−1} kg^{−0.75})\), and RE were higher in the male participants compared with the females (P < 0.01). The % of \(VO_2\) at \(v_{LT}\) was lower in the males compared with the females (P < 0.01). No differences between gender were detected for the \(v_{LT}\) (P = 0.17) and % of \(VO_2\) at \(v_{LT}\) (P = 0.42). This study is one of the first to provide a broad spectrum of data to classify nearly 500 elite athletes aged 12–21 years of both gender and different disciplines. KW - performance KW - data KW - competition KW - reference values Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126275 VL - 4 IS - 544 ER - TY - JOUR A1 - Zinner, Christoph A1 - Hauser, Anna A1 - Born, Dennis-Peter A1 - Wehrlin, Jon P. A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Influence of Hypoxic Interval Training and Hyperoxic Recovery on Muscle Activation and Oxygenation in Connection with Double-Poling Exercise JF - PLoS One N2 - Here, we evaluated the influence of breathing oxygen at different partial pressures during recovery from exercise on performance at sea-level and a simulated altitude of 1800 m, as reflected in activation of different upper body muscles, and oxygenation of the m. triceps brachii. Ten well-trained, male endurance athletes (25.3±4.1 yrs; 179.2±4.5 cm; 74.2±3.4 kg) performed four test trials, each involving three 3-min sessions on a double-poling ergometer with 3-min intervals of recovery. One trial was conducted entirely under normoxic (No) and another under hypoxic conditions \((Ho; F_iO_2 = 0.165)\). In the third and fourth trials, the exercise was performed in normoxia and hypoxia, respectively, with hyperoxic recovery \((HOX; F_iO_2 = 1.00)\) in both cases. Arterial hemoglobin saturation was higher under the two HOX conditions than without HOX (p<0.05). Integrated muscle electrical activity was not influenced by the oxygen content (best d = 0.51). Furthermore, the only difference in tissue saturation index measured via near-infrared spectroscopy observed was between the recovery periods during the NoNo and HoHOX interventions (P<0.05, d = 0.93). In the case of HoHo the athletes’ \(P_{mean}\) declined from the first to the third interval (P < 0.05), whereas Pmean was unaltered under the HoHOX, NoHOX and NoNo conditions. We conclude that the less pronounced decline in \(P_{mean}\) during 3 x 3-min double-poling sprints in normoxia and hypoxia with hyperoxic recovery is not related to changes in muscle activity or oxygenation. Moreover, we conclude that hyperoxia \((F_iO_2 = 1.00)\) used in conjunction with hypoxic or normoxic work intervals may serve as an effective aid when inhaled during the subsequent recovery intervals. KW - triceps KW - bood KW - medical hypoxia KW - blood KW - arms KW - hyperoxia KW - breathing KW - near-infrared spectroscopy Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126299 VL - 10 IS - 10 ER - TY - JOUR A1 - Born, Dennis-Peter A1 - Holmberg, Hans-Christer A1 - Goernet, Florian A1 - Sperlich, Billy T1 - A novel compression garment with adhesive silicone stripes improves repeated sprint performance – a multi-experimental approach on the underlying mechanisms JF - BMC Sports Science, Medicine and Rehabilitation N2 - Background Repeated sprint performance is determined by explosive production of power, as well as rapid recovery between successive sprints, and there is evidence that compression garments and sports taping can improve both of these factors. Methods In each of two sub-studies, female athletes performed two sets of 30 30-m sprints (one sprint per minute), one set wearing compression garment with adhesive silicone stripes (CGSS) intended to mimic taping and the other with normal clothing, in randomized order. Sub-study 1 (n = 12) focused on cardio-respiratory, metabolic, hemodynamic and perceptual responses, while neuronal and biomechanical parameters were examined in sub-study 2 (n = 12). Results In both sub-studies the CGSS improved repeated sprint performance during the final 10 sprints (best P < 0.01, d = 0.61). None of the cardio-respiratory or metabolic variables monitored were altered by wearing this garment (best P = 0.06, d = 0.71). Also during the final 10 sprints, rating of perceived exertion by the upper leg muscles was reduced (P = 0.01, d = 1.1), step length increased (P = 0.01, d = 0.91) and activation of the m. rectus femoris elevated (P = 0.01, d = 1.24), while the hip flexion angle was lowered throughout the protocol (best P < 0.01, d = 2.28) and step frequency (best P = 0.34, d = 0.2) remained unaltered. Conclusion Although the physiological parameters monitored were unchanged, the CGSS appears to improve performance during 30 30-m repeated sprints by reducing perceived exertion and altering running technique. KW - textile KW - tissue saturation index KW - venous system KW - video analysis KW - oxygen uptake KW - blood flow KW - clothing KW - oscillation KW - oxygenation Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120591 SN - 2052-1847 VL - 6 IS - 21 ER - TY - JOUR A1 - Stöggl, Thomas L. A1 - Sperlich, Billy T1 - The training intensity distribution among well-trained and elite endurance athletes JF - Frontiers in Physiology N2 - Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a "pyramidal" TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called "polarized" TID (i.e., significant % of HVLIT and high intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies. KW - pyramidal retrospective KW - high volume KW - prospective KW - high intensity training KW - adaptations KW - cyclists KW - speed skaters KW - skeletal-muscle KW - polarized training KW - world championships KW - low intensity KW - optimize performance KW - blood lactate KW - cross-country skiers KW - aerobic performance KW - anaerobic threshold KW - threshold training Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138883 VL - 6 IS - 295 ER - TY - JOUR A1 - Born, Dennis-Peter A1 - Holmberg, Hans-Christer A1 - Goernert, Florian A1 - Sperlich, Billy T1 - A novel compression garment with adhesive silicone stripes improves repeated sprint performance – a multi-experimental approach on the underlying mechanisms JF - BMC Sports Science, Medicine and Rehabilitation N2 - Background Repeated sprint performance is determined by explosive production of power, as well as rapid recovery between successive sprints, and there is evidence that compression garments and sports taping can improve both of these factors. Methods In each of two sub-studies, female athletes performed two sets of 30 30-m sprints (one sprint per minute), one set wearing compression garment with adhesive silicone stripes (CGSS) intended to mimic taping and the other with normal clothing, in randomized order. Sub-study 1 (n = 12) focused on cardio-respiratory, metabolic, hemodynamic and perceptual responses, while neuronal and biomechanical parameters were examined in sub-study 2 (n = 12). Results In both sub-studies the CGSS improved repeated sprint performance during the final 10 sprints (best P < 0.01, d = 0.61). None of the cardio-respiratory or metabolic variables monitored were altered by wearing this garment (best P = 0.06, d = 0.71). Also during the final 10 sprints, rating of perceived exertion by the upper leg muscles was reduced (P = 0.01, d = 1.1), step length increased (P = 0.01, d = 0.91) and activation of the m. rectus femoris elevated (P = 0.01, d = 1.24), while the hip flexion angle was lowered throughout the protocol (best P < 0.01, d = 2.28) and step frequency (best P = 0.34, d = 0.2) remained unaltered. Conclusion Although the physiological parameters monitored were unchanged, the CGSS appears to improve performance during 30 30-m repeated sprints by reducing perceived exertion and altering running technique. KW - tissue saturation index KW - blood flow KW - clothing KW - oscillation KW - oxygenation KW - oxygen uptake KW - textile KW - venous system KW - video analysis Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116995 UR - http://www.biomedcentral.com/2052-1847/6/21 VL - 6 IS - 21 ER - TY - JOUR A1 - Stöggl, Thomas A1 - Sperlich, Billy T1 - Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training JF - Frontiers in Physiology N2 - Endurance athletes integrate four conditioning concepts in their training programs: high-volume training (HVT), “threshold-training” (THR), high-intensity interval training (HIIT) and a combination of these aforementioned concepts known as polarized training (POL). The purpose of this study was to explore which of these four training concepts provides the greatest response on key components of endurance performance in well-trained endurance athletes. Methods: Forty eight runners, cyclists, triathletes, and cross-country skiers (peak oxygen uptake: (VO2peak): 62.6 ± 7.1 mL·min−1·kg−1) were randomly assigned to one of four groups performing over 9 weeks. An incremental test, work economy and a VO2peak tests were performed. Training intensity was heart rate controlled. Results: POL demonstrated the greatest increase in VO2peak (+6.8 ml·min·kg−1 or 11.7%, P < 0.001), time to exhaustion during the ramp protocol (+17.4%, P < 0.001) and peak velocity/power (+5.1%, P < 0.01). Velocity/power at 4 mmol·L−1 increased after POL (+8.1%, P < 0.01) and HIIT (+5.6%, P < 0.05). No differences in pre- to post-changes of work economy were found between the groups. Body mass was reduced by 3.7% (P < 0.001) following HIIT, with no changes in the other groups. With the exception of slight improvements in work economy in THR, both HVT and THR had no further effects on measured variables of endurance performance (P > 0.05). Conclusion: POL resulted in the greatest improvements in most key variables of endurance performance in well-trained endurance athletes. THR or HVT did not lead to further improvements in performance related variables. KW - work economy KW - time to exhaustion KW - peak oxygen uptake KW - peak power KW - lactate threshold Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117007 VL - 5 IS - 33 ER - TY - JOUR A1 - Düking, Peter A1 - Holmberg, Hans‑Christer A1 - Kunz, Philipp A1 - Leppich, Robert A1 - Sperlich, Billy T1 - Intra-individual physiological response of recreational runners to different training mesocycles: a randomized cross-over study JF - European Journal of Applied Physiology N2 - Purpose Pronounced differences in individual physiological adaptation may occur following various training mesocycles in runners. Here we aimed to assess the individual changes in performance and physiological adaptation of recreational runners performing mesocycles with different intensity, duration and frequency. Methods Employing a randomized cross-over design, the intra-individual physiological responses [i.e., peak (\(\dot{VO}_{2peak}\)) and submaximal (\(\dot{VO}_{2submax}\)) oxygen uptake, velocity at lactate thresholds (V\(_2\), V\(_4\))] and performance (time-to-exhaustion (TTE)) of 13 recreational runners who performed three 3-week sessions of high-intensity interval training (HIIT), high-volume low-intensity training (HVLIT) or more but shorter sessions of HVLIT (high-frequency training; HFT) were assessed. Results \(\dot{VO}_{2submax}\), V\(_2\), V\(_4\) and TTE were not altered by HIIT, HVLIT or HFT (p > 0.05). \(\dot{VO}_{2peak}\) improved to the same extent following HVLIT (p = 0.045) and HFT (p = 0.02). The number of moderately negative responders was higher following HIIT (15.4%); and HFT (15.4%) than HVLIT (7.6%). The number of very positive responders was higher following HVLIT (38.5%) than HFT (23%) or HIIT (7.7%). 46% of the runners responded positively to two mesocycles, while 23% did not respond to any. Conclusion On a group level, none of the interventions altered \(\dot{VO}_{2submax}\), V\(_2\), V\(_4\) or TTE, while HVLIT and HFT improved \(\dot{VO}_{2peak}\). The mean adaptation index indicated similar numbers of positive, negative and non-responders to HIIT, HVLIT and HFT, but more very positive responders to HVLIT than HFT or HIIT. 46% responded positively to two mesocycles, while 23% did not respond to any. These findings indicate that the magnitude of responses to HIIT, HVLIT and HFT is highly individual and no pattern was apparent. KW - cardiorespiratory fitness KW - endurance KW - personalized training Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235022 SN - 1439-6319 VL - 120 ER - TY - JOUR A1 - Bauer, Nikolai A1 - Sperlich, Billy A1 - Holmberg, Hans-Christer A1 - Engel, Florian A. T1 - Effects of High-Intensity Interval Training in School on the Physical Performance and Health of Children and Adolescents: A Systematic Review with Meta-Analysis JF - Sports Medicine - Open N2 - Objectives To assess the impact of HIIT performed at school, i.e. both in connection with physical education (intra-PE) and extracurricular sports activities (extra-PE), on the physical fitness and health of children and adolescents. Methods PubMed and SPORTDiscus were searched systematically utilizing the following criteria for inclusion: (1) healthy children and adolescents (5–18 years old) of normal weight; (2) HIIT performed intra- and/or extra-PE for at least 5 days at an intensity ≥ 80% of maximal heart rate (HR\(_{max}\)) or peak oxygen uptake (VO\(_{2peak}\)) or as Functional HIIT; (3) comparison with a control (HIIT versus alternative interventions); and (4) pre- and post-analysis of parameters related to physical fitness and health. The outcomes with HIIT and the control interventions were compared utilizing Hedges’ g effect size (ES) and associated 95% confidence intervals. Results Eleven studies involving 707 participants who performed intra-PE and 388 participants extra-PE HIIT were included. In comparison with the control interventions, intra-PE HIIT improved mean ES for neuromuscular and anaerobic performance (ES jump performance: 5.89 ± 5.67 (range 1.88–9.90); ES number of push-ups: 6.22 (range n.a.); ES number of sit-ups: 2.66 ± 2.02 (range 1.24–4.09)), as well as ES fasting glucose levels (− 2.68 (range n.a.)) more effectively, with large effect sizes. Extra-PE HIIT improved mean ES for neuromuscular and anaerobic performance (ES jump performance: 1.81 (range n.a.); ES number of sit-ups: 2.60 (range n.a.)) to an even greater extent, again with large effect sizes. Neither form of HIIT was more beneficial for parameters related to cardiorespiratory fitness than the control interventions. Conclusion Compared to other forms of exercise (e.g. low-to-moderate-intensity running or walking), both intra- and extra-PE HIIT result in greater improvements in neuromuscular and anaerobic performance, as well as in fasting levels of glucose in school children. KW - adolescents KW - health-related fitness KW - physical fitness KW - children KW - high-intensity interval training KW - physical education Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301205 SN - 2199-1170 VL - 8 IS - 1 ER - TY - JOUR A1 - Sareban, Mahdi A1 - Winkert, Kay A1 - Sperlich, Billy A1 - Berger, Marc M. A1 - Niebauer, Josef A1 - Steinacker, Jürgen M. A1 - Treff, Gunnar T1 - Speckle tracking-derived bi-atrial strain before and after eleven weeks of training in elite rowers JF - Scientific Reports N2 - The left (LA) and right (RA) atria undergo adaptive remodeling in response to hemodynamic stress not only induced by endurance exercise but also as part of several cardiovascular diseases thereby confounding differential diagnosis. Echocardiographic assessment of the atria with novel speckle tracking (STE)-derived variables broadens the diagnostic spectrum compared to conventional analyses and has the potential to differentiate physiologic from pathologic changes. The purpose of this study was to assess and categorize baseline values of bi-atrial structure and function in elite rowers according to recommended cutoffs, and to assess the cardiac changes occurring with endurance training. Therefore, fifteen elite rowers underwent 2D-echocardiographic analysis of established variables of cardiac structure and function as well as STE-derived variables of bi-atrial function. Measurements were performed at baseline and after eleven weeks of extensive training. 40% of athletes displayed mildly enlarged LA and 47% mildly enlarged RA at baseline, whereas no athlete fell below the lower reference values of LA and RA reservoir strain. Average power during a 2000 m ergometer rowing test (P2000 m) improved from 426 +/- 39 W to 442 +/- 34 W (p = 0.010) but there were no changes of echocardiographic variables following training. In elite rowers, longitudinal bi-atrial strain assessment indicates normal resting function of structurally enlarged atria and thereby may assist to differentiate between exercise-induced versus disease-associated structural cardiac changes in which function is commonly impaired. KW - Elite Rowers KW - Reservoir Strain KW - Lower Reference Value KW - Rowing Ergometer KW - Strain Assessment KW - Cardiovascular biology KW - Risk factors Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227362 VL - 8 ER - TY - JOUR A1 - Engel, Florian Azad A1 - Ackermann, Alexander A1 - Chtourou, Hamdi A1 - Sperlich, Billy T1 - High-Intensity Interval Training Performed by Young Athletes: A Systematic Review and Meta-Analysis JF - Frontiers in Physiology N2 - Background: High-intensity interval training (HIIT) is as a time-efficient alternative to moderate- or low-intensity continuous exercise for improving variables related to endurance and anaerobic performance in young and adolescent athletes. Objectives: To assess original research about enhancement of endurance and anaerobic exercise performance in young and adolescent athletes performing HIIT. Method: Relevant articles published in peer-reviewed journals were retrieved from the electronic databases PubMed and SPORTDiscus in December 2017. Inclusion criteria were: (i) controlled trials (HIIT vs. alternative training protocol) with pre-post design; (ii) healthy young athletes (≤18 years); (iii) assessing variables related to endurance and exercise performance. Hedges' g effect size (ES), and associated 95% confidence intervals were calculated for comparison of any outcome between experimental (HIIT) and alternative training protocol. Results: Twenty four studies, involving 577 athletes (mean age: 15.5 ± 2.2 years), were included in this review. HIIT exerted no or small positive mean ES on peak oxygen uptake (VO2peak), running performance, repeated sprint ability, jumping performance and submaximal heart rate. Although the mean ES for changes in VO2peak with HIIT is small (mean g = 0.10±0.28), the average increase in VO2peak from pre to post HIIT-interventions were 7.2 ± 6.9% vs. 4.3 ± 6.9% with any other alternative intervention. HIIT largely and positively affected running speed and oxygen consumption at various lactate- or ventilatory-based thresholds, as well as for sprint running performance. Calculations showed negative mean ES for change-of-direction ability (large), and peak blood lactate concentrations (small). Mean duration per training session for HIIT was shorter than for control interventions (28 ± 15 min vs. 38 ± 24 min). Conclusion: The present findings suggest that young athletes performing HIIT may improve certain important variables related to aerobic, as well as anaerobic, performance. With HIIT, most variables related to endurance improved to a higher extent, compared to alternative training protocols. However, based on ES, HIIT did not show clear superiority to the alternative training protocols. Nevertheless, young athletes may benefit from HIIT as it requires less time per training session leaving more time for training sport specific skills. KW - adolescents KW - physical fitness KW - aerobic training KW - peak oxygen uptake KW - training intensity Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189173 SN - 1664-042X VL - 9 ER - TY - JOUR A1 - Kunz, Philipp A1 - Zinner, Christoph A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Intra- and post-match time-course of indicators related to perceived and performance fatigability and recovery in elite youth soccer players JF - Frontiers in Physiology N2 - PurposeOur aims were to examine (i) the internal load during simulated soccer match-play by elite youth players; and (ii) the time-course of subsequent recovery from perceived and performance fatigability. MethodsEleven male youth players (16 ± 1 years, 178 ± 7 cm, 67 ± 7 kg) participated in a 2 × 40-min simulated soccer match, completing 30 rounds (160 s each) with every round including multidirectional and linear sprinting (LS20m), jumping (CMJ) and running at different intensities. During each round, LS20m, CMJ, agility, heart rate (HR), oxygen uptake (VO2), energy expenditure (EE), substrate utilization and perceived exertion RPE were assessed. In addition, the blood level of lactate (Lac) was obtained after each of the five rounds. Creatine kinase (CK) concentration, maximal voluntary isometric knee extension and flexion, CMJ, number of skippings in 30 s, and subjective ratings on the Acute Recovery and Stress Scale (ARSS) were examined before and immediately, 24 and 48 h after the simulation. Results: During the game %HR\(_{peak}\) (p < 0.05, d = 1.08), %VO2\(_{peak}\) (p < 0.05; d = 0.68), Lac (p < 0.05, d = 2.59), RPE\(_{total}\) (p < 0.05, d = 4.59), and RPE\(_{legs}\) (p < 0.05, d = 4.45) all increased with time during both halves (all p < 0.05). Agility improved (p < 0.05, d = 0.70) over the time-course of the game, with no changes in LS20m (p ≥ 0.05, d = 0.34) or CMJ (p ≥ 0.05, d = 0.27). EE was similar during both halves (528 ± 58 vs. 514 ± 61 kcal; p = 0.60; d = 0.23), with 62% (second half: 65%) carbohydrate, 9% (9%) protein and 26% (27%) fat utilization. With respect to recovery, maximal voluntary knee extension (p ≥ 0.05, d = 0.50) and flexion force (p ≥ 0.05, d = 0.19), CMJ (p ≥ 0.05, d = 0.13), number of ground contacts (p ≥ 0.05, d = 0.57) and average contact time (p ≥ 0.05, d = 0.39) during 30-s of skipping remained unaltered 24 and 48 h after the game. Most ARSS dimensions of load (p < 0.05, d = 3.79) and recovery (p < 0.05, d = 3.22) returned to baseline levels after 24 h of recovery. Relative to baseline values, CK was elevated immediately and 24 h after (p < 0.05, d = 2.03) and normalized 48 h later. ConclusionIn youth soccer players the simulated match evoked considerable circulatory, metabolic and perceptual load, with an EE of 1042 ± 118 kcal. Among the indicators of perceived and performance fatigability examined, the level of CK and certain subjective ratings differed considerably immediately following or 24–48 h after a 2 × 40-min simulated soccer match in comparison to baseline. Accordingly, monitoring these variables may assist coaches in assessing a U17 player’s perceived and performance fatigability in connection with scheduling training following a soccer match. KW - soccer (football) KW - youth KW - match load KW - fatigue KW - intermittent exercise KW - performance Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-195657 SN - 1664-042X VL - 10 IS - 1383 ER - TY - JOUR A1 - Chtourou, Hamdi A1 - Engel, Florian Azad A1 - Fakhfakh, Hassen A1 - Fakhfakh, Hazem A1 - Hammouda, Omar A1 - Ammar, Achraf A1 - Trabelsi, Khaled A1 - Souissi, Nizar A1 - Sperlich, Billy T1 - Diurnal Variation of Short-Term Repetitive Maximal Performance and Psychological Variables in Elite Judo Athletes JF - Frontiers in Physiology N2 - Objectives: The aim of this study was to examine the effect of time of day on short-term repetitive maximal performance and psychological variables in elite judo athletes. Methods: Fourteen Tunisian elite male judokas (age: 21 ± 1 years, height:172 ± 7 cm, body-mass: 70.0 ± 8.1 kg) performed a repeated shuttle sprint and jump ability (RSSJA) test (6 m × 2 m × 12.5 m every 25-s incorporating one countermovement jump (CMJ) between sprints) in the morning (7:00 a.m.) and afternoon (5:00 p.m.). Psychological variables (Profile of mood states (POMS-f) and Hooper questionnaires) were assessed before and ratings of perceived exertion (RPE) immediately after the RSSJA. Results: Sprint times (p > 0.05) of the six repetition, fatigue index of sprints (p > 0.05) as well as mean (p > 0.05) jump height and fatigue index (p > 0.05) of CMJ did not differ between morning and afternoon. No differences were observed between the two times-of-day for anxiety, anger, confusion, depression, fatigue, interpersonal relationship, sleep, and muscle soreness (p > 0.05). Jump height in CMJ 3 and 4 (p < 0.05) and RPE (p < 0.05) and vigor (p < 0.01) scores were higher in the afternoon compared to the morning. Stress was higher in the morning compared to the afternoon (p < 0.01). Conclusion: In contrast to previous research, repeated sprint running performance and mood states of the tested elite athletes showed no-strong dependency of time-of-day of testing. A possible explanation can be the habituation of the judo athletes to work out early in the morning. KW - circadian rhythm KW - repeated sprint running KW - repeated exercise KW - mood KW - fatigue Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189269 SN - 1664-042X VL - 9 ER - TY - JOUR A1 - Kunz, Philipp A1 - Azad Engel, Florian A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - A meta-comparison of the effects of high-intensity interval training to those of small-sided games and other training protocols on parameters related to the physiology and performance of youth soccer players JF - Sports Medicine - Open N2 - Background High-intensity interval training (HIIT) is frequently employed to improve the endurance of various types of athletes. To determine whether youth soccer players may benefit from the intermittent load and time efficiency of HIIT, we performed a meta-analysis of the relevant scientific literature. Objectives Our primary objective was to compare changes in various physiological parameters related to the performance of youth soccer players in response to running-based HIIT to the effects of other common training protocols (i.e., small-sided games, technical training and soccer-specific training, or high-volume endurance training). A secondary objective was to compare specifically running-based HIIT to a soccer-specific form of HIIT known as small-sided games (SSG) in this same respect, since this latter type of training is being discussed extensively by coaches. Method A systematic search of the PubMed, SPORTDiscus, and Web of Science databases was performed in August of 2017 and updated during the review process in December of 2018. The criteria for inclusion of articles for analysis were as follows: (1) comparison of HIIT to SSG or some other training protocol employing a pre-post design, (2) involvement of healthy young athletes (≤ 18 years old), and (3) assessment of variables related to endurance or soccer performance. Hedges’ g effect size (dppc2) and associated 95% confidence intervals for the comparison of the responses to HIIT and other interventions were calculated. Results Nine studies, involving 232 young soccer players (mean age 16.2 ± 1.6 years), were examined. Endurance training in the form of HIIT or SSG produced similar positive effects on most parameters assessed, including peak oxygen uptake and maximal running performance during incremental running (expressed as Vmax or maximal aerobic speed (MAS)), shuttle runs (expressed as the distance covered or time to exhaustion), and time-trials, as well as submaximal variables such as running economy and running velocity at the lactate threshold. HIIT induced a moderate improvement in soccer-related tests involving technical exercises with the soccer ball and other game-specific parameters (i.e., total distance covered, number of sprints, and number of involvements with the ball). Neuromuscular parameters were largely unaffected by HIIT or SSG. Conclusion The present meta-analysis indicates that HIIT and SSG have equally beneficial impacts on variables related to the endurance and soccer-specific performance of youth soccer players, but little influence on neuromuscular performance. KW - adolescents KW - children KW - conditioning KW - endurance KW - repeated sprint Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200332 VL - 5 ER - TY - JOUR A1 - Güder, Gülmisal A1 - Wilkesmann, Joana A1 - Scholz, Nina A1 - Leppich, Robert A1 - Düking, Peter A1 - Sperlich, Billy A1 - Rost, Christian A1 - Frantz, Stefan A1 - Morbach, Caroline A1 - Sahiti, Floran A1 - Stefenelli, Ulrich A1 - Breunig, Margret A1 - Störk, Stefan T1 - Establishing a cardiac training group for patients with heart failure: the "HIP-in-Würzburg" study JF - Clinical Research in Cardiology N2 - Background Exercise training in heart failure (HF) is recommended but not routinely offered, because of logistic and safety-related reasons. In 2020, the German Society for Prevention&Rehabilitation and the German Society for Cardiology requested establishing dedicated ""HF training groups."" Here, we aimed to implement and evaluate the feasibility and safety of one of the first HF training groups in Germany. Methods Twelve patients (three women) with symptomatic HF (NYHA class II/III) and an ejection fraction ≤ 45% participated and were offered weekly, physician-supervised exercise training for 1 year. Patients received a wrist-worn pedometer (M430 Polar) and underwent the following assessments at baseline and after 4, 8 and 12 months: cardiopulmonary exercise test, 6-min walk test, echocardiography (blinded reading), and quality of life assessment (Kansas City Cardiomyopathy Questionnaire, KCCQ). Results All patients (median age [quartiles] 64 [49; 64] years) completed the study and participated in 76% of the offered 36 training sessions. The pedometer was worn ≥ 1000 min per day over 86% of the time. No cardiovascular events occurred during training. Across 12 months, NT-proBNP dropped from 986 pg/ml [455; 1937] to 483 pg/ml [247; 2322], and LVEF increased from 36% [29;41] to 41% [32;46]%, (p for trend = 0.01). We observed no changes in exercise capacity except for a subtle increase in peak VO2% predicted, from 66.5 [49; 77] to 67 [52; 78]; p for trend = 0.03. The physical function and social limitation domains of the KCCQ improved from 60 [54; 82] to 71 [58; 95, and from 63 [39; 83] to 78 [64; 92]; p for trend = 0.04 and = 0.01, respectively. Positive trends were further seen for the clinical and overall summary scores. Conclusion This pilot study showed that the implementation of a supervised HF-exercise program is feasible, safe, and has the potential to improve both quality of life and surrogate markers of HF severity. This first exercise experiment should facilitate the design of risk-adopted training programs for patients with HF. KW - m exercise training KW - heart failure KW - cardiac training group KW - heart failure training group Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266678 SN - 1861-0692 VL - 111 ER - TY - JOUR A1 - Düking, Peter A1 - Giessing, Laura A1 - Frenkel, Marie Ottilie A1 - Koehler, Karsten A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Wrist-Worn Wearables for Monitoring Heart Rate and Energy Expenditure While Sitting or Performing Light-to-Vigorous Physical Activity: Validation Study JF - JMIR mhealth and uhealth N2 - Background: Physical activity reduces the incidences of noncommunicable diseases, obesity, and mortality, but an inactive lifestyle is becoming increasingly common. Innovative approaches to monitor and promote physical activity are warranted. While individual monitoring of physical activity aids in the design of effective interventions to enhance physical activity, a basic prerequisite is that the monitoring devices exhibit high validity. Objective: Our goal was to assess the validity of monitoring heart rate (HR) and energy expenditure (EE) while sitting or performing light-to-vigorous physical activity with 4 popular wrist-worn wearables (Apple Watch Series 4, Polar Vantage V, Garmin Fenix 5, and Fitbit Versa). Methods: While wearing the 4 different wearables, 25 individuals performed 5 minutes each of sitting, walking, and running at different velocities (ie, 1.1 m/s, 1.9 m/s, 2.7 m/s, 3.6 m/s, and 4.1 m/s), as well as intermittent sprints. HR and EE were compared to common criterion measures: Polar-H7 chest belt for HR and indirect calorimetry for EE. Results: While monitoring HR at different exercise intensities, the standardized typical errors of the estimates were 0.09-0.62, 0.13-0.88, 0.62-1.24, and 0.47-1.94 for the Apple Watch Series 4, Polar Vantage V, Garmin Fenix 5, and Fitbit Versa, respectively. Depending on exercise intensity, the corresponding coefficients of variation were 0.9%-4.3%, 2.2%-6.7%, 2.9%-9.2%, and 4.1%-19.1%, respectively, for the 4 wearables. While monitoring EE at different exercise intensities, the standardized typical errors of the estimates were 0.34-1.84, 0.32-1.33, 0.46-4.86, and 0.41-1.65 for the Apple Watch Series 4, Polar Vantage V, Garmin Fenix 5, and Fitbit Versa, respectively. Depending on exercise intensity, the corresponding coefficients of variation were 13.5%-27.1%, 16.3%-28.0%, 15.9%-34.5%, and 8.0%-32.3%, respectively. Conclusions: The Apple Watch Series 4 provides the highest validity (ie, smallest error rates) when measuring HR while sitting or performing light-to-vigorous physical activity, followed by the Polar Vantage V, Garmin Fenix 5, and Fitbit Versa, in that order. The Apple Watch Series 4 and Polar Vantage V are suitable for valid HR measurements at the intensities tested, but HR data provided by the Garmin Fenix 5 and Fitbit Versa should be interpreted with caution due to higher error rates at certain intensities. None of the 4 wrist-worn wearables should be employed to monitor EE at the intensities and durations tested." KW - cardiorespiratory fitness KW - innovation KW - smartwatch KW - technology KW - wearable KW - digital health Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229413 VL - 8 IS - 5 ER - TY - JOUR A1 - Engel, Florian A. A1 - Wagner, Matthias Oliver A1 - Schelhorn, Franziska A1 - Deubert, Felix A1 - Leutzsch, Sascha A1 - Stolz, Alexander A1 - Sperlich, Billy T1 - Classroom-Based Micro-Sessions of Functional High-Intensity Circuit Training Enhances Functional Strength but Not Cardiorespiratory Fitness in School Children — A Feasibility Study JF - Frontiers in Public Health N2 - The present study assessed the short-term effect of 6 min classroom-based micro-sessions of multi-joint functional high-intensity circuit training (FunctionalHIIT) performed by students during regular classes on parameters related to functional strength and cardiorespiratory fitness. In this randomized controlled 4-week study, 17 students (11 male; 6 female; age: 11.6 ± 0.2 years) performed 6 min of FunctionalHIIT (targeting >17 on the Borg scale) 4 days per week during regular school classes and 18 students (11 male; 7 female; age: 11.7 ± 0.3 years) served as control group (CG) without any additional in-class physical activity. The FunctionalHIIT group completed 86% of all planned sessions (mean duration: 6.0 ± 1.5 min) with a mean RPE of 17.3 ± 2.1. Body height, mass and BMI did not differ between the groups at baseline or between pre- and post-testing (p > 0.05; eta2 ≤ 0.218). The performances in lateral jumping (p < 0.000; part eta2 = 0.382; Δ% 4.6 ± 8.6), sit-ups (p < 0.000; part eta2 = 0.485; Δ% 3.1 ± 8.6) and 20-m sprints (p < 0.000; part eta2 = 0.691; Δ% 15.8 ± 5.4) improved in both groups with greater increase following FunctionalHIIT. No baseline differences and no interaction effects occurred in performance of 6 min run, flexibility, push-ups, balance, and long jump. Classroom-based FunctionalHIIT sessions, performed 4 days per week during 4 weeks did not improve variables related to aerobic endurance performance but enhanced certain parameters of functional strength in schoolchildren. As time is limited in the educational system of schools, FunctionalHIIT during regular school classes could offer a new perspective for increasing functional strength in schoolchildren. KW - aerobic fitness KW - exercise intervention KW - functional training KW - interval training KW - physical activity promotion Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-195669 SN - 2296-2565 VL - 7 IS - 291 ER - TY - JOUR A1 - Becker, Manuel A1 - Sperlich, Billy A1 - Zinner, Christoph A1 - Achtzehn, Silvia T1 - Intra-Individual and Seasonal Variation of Selected Biomarkers for Internal Load Monitoring in U-19 Soccer Players JF - Frontiers in Physiology N2 - The aim of this study was to investigate inter-day and -week as well as intra- and inter-individual variation of selected biomarkers in high-performance youth soccer players to assist practitioners interpreting player’s internal load to counteract underperformance and unwanted health risks. Eleven male youth soccer players were tested multiple times during two 3-week periods at midpoint (3-wkmid) and at the end (3-wkend) of the first half of a German under-19 1. Bundesliga season. The levels of creatine kinase (CK), urea, and C-reactive protein (CRP) were measured during 3-wkmid and 3-wkend each Monday, Wednesday, and Friday. In 3-wkmid the CK median was 14% higher (241 vs. 212 U/L) compared to 3-wkend (P = 0.26, ES = 0.16). Overall, the medians of CK, urea (P = 0.59, ES = 0.08), and CRP (P = 0.56, ES = 0.10) during 3-wkmid did not differ to the values of 3-wkend. Daily coefficient of variations (CVs) ranged from 22 to 71% (CK), 17 to 37% (urea), and 9 to 164% (CRP). Individual medians ranged from 101 to 350 U/L (CK), 23 to 50 mg/dL (urea), and 0.6 to 1.1 mg/L (CRP). High intra-individual variability was demonstrated by large intra-individual CVs (medians: CK 50%, urea 18%, and CRP 45%). Our data show (i) large inter-day and inter-week variability of all biomarkers, depending on the external load and (ii) considerable inter- and intra-individual parameter variations. Creatine kinase concentrations could sensitively reflect soccer-specific loads during the season. KW - biomarker variability KW - creatine kinase KW - soccer KW - youth soccer KW - internal load KW - monitoring KW - point of care testing Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-209616 SN - 1664-042X VL - 11 IS - 838 ER - TY - JOUR A1 - McIlroy, Benjamin A1 - Passfield, Louis A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Virtual training of endurance cycling – A summary of strengths, weaknesses, opportunities and threats JF - Frontiers in Sports and Active Living N2 - Virtual online training has emerged as one of the top 20 worldwide fitness trends for 2021 and continues to develop rapidly. Although this allows the cycling community to engage in virtual training and competition, critical evaluation of virtual training platforms is limited. Here, we discuss the strengths, weaknesses, opportunities and threats associated with virtual training technology and cycling in an attempt to enhance awareness of such aspects. Strengths include immersive worlds, innovative drafting mechanics, and versatility. Weaknesses include questionable data accuracy, inadequate strength and reliability of power-speed algorithms. Opportunities exist for expanding strategic partnerships with major cycling races, brands, and sponsors and improving user experience with the addition of video capture and “e-coaching.” Threats are present in the form of cheating during competition, and a lack of uptake and acceptance by a broader community. KW - algorithms KW - cycling KW - e-coach KW - e-health KW - ergometer KW - simulation KW - virtual training KW - SWOT Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258876 VL - 3 ER - TY - JOUR A1 - Davidson, Padraig A1 - Düking, Peter A1 - Zinner, Christoph A1 - Sperlich, Billy A1 - Hotho, Andreas T1 - Smartwatch-Derived Data and Machine Learning Algorithms Estimate Classes of Ratings of Perceived Exertion in Runners: A Pilot Study JF - Sensors N2 - The rating of perceived exertion (RPE) is a subjective load marker and may assist in individualizing training prescription, particularly by adjusting running intensity. Unfortunately, RPE has shortcomings (e.g., underreporting) and cannot be monitored continuously and automatically throughout a training sessions. In this pilot study, we aimed to predict two classes of RPE (≤15 “Somewhat hard to hard” on Borg’s 6–20 scale vs. RPE >15 in runners by analyzing data recorded by a commercially-available smartwatch with machine learning algorithms. Twelve trained and untrained runners performed long-continuous runs at a constant self-selected pace to volitional exhaustion. Untrained runners reported their RPE each kilometer, whereas trained runners reported every five kilometers. The kinetics of heart rate, step cadence, and running velocity were recorded continuously ( 1 Hz ) with a commercially-available smartwatch (Polar V800). We trained different machine learning algorithms to estimate the two classes of RPE based on the time series sensor data derived from the smartwatch. Predictions were analyzed in different settings: accuracy overall and per runner type; i.e., accuracy for trained and untrained runners independently. We achieved top accuracies of 84.8 % for the whole dataset, 81.8 % for the trained runners, and 86.1 % for the untrained runners. We predict two classes of RPE with high accuracy using machine learning and smartwatch data. This approach might aid in individualizing training prescriptions. KW - artificial intelligence KW - endurance KW - exercise intensity KW - precision training KW - prediction KW - wearable Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-205686 SN - 1424-8220 VL - 20 IS - 9 ER - TY - JOUR A1 - Düking, Peter A1 - Hotho, Andreas A1 - Holmberg, Hans-Christer A1 - Fuss, Franz Konstantin A1 - Sperlich, Billy T1 - Comparison of Non-Invasive Individual Monitoring of the Training and Health of Athletes with Commercially Available Wearable Technologies JF - Frontiers in Physiology N2 - Athletes adapt their training daily to optimize performance, as well as avoid fatigue, overtraining and other undesirable effects on their health. To optimize training load, each athlete must take his/her own personal objective and subjective characteristics into consideration and an increasing number of wearable technologies (wearables) provide convenient monitoring of various parameters. Accordingly, it is important to help athletes decide which parameters are of primary interest and which wearables can monitor these parameters most effectively. Here, we discuss the wearable technologies available for non-invasive monitoring of various parameters concerning an athlete's training and health. On the basis of these considerations, we suggest directions for future development. Furthermore, we propose that a combination of several wearables is most effective for accessing all relevant parameters, disturbing the athlete as little as possible, and optimizing performance and promoting health. KW - sports technology KW - wearable technologies KW - performance parameters KW - health monitoring KW - performance monitoring Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165516 VL - 7 IS - 71 ER - TY - JOUR A1 - Trabelsi, Khaled A1 - Ammar, Achraf A1 - Boukhris, Omar A1 - Glenn, Jordan M. A1 - Bott, Nick A1 - Stannard, Stephen R. A1 - Engel, Florian A. A1 - Sperlich, Billy A1 - Garbarino, Sergio A1 - Bragazzi, Nicola L. A1 - Shephard, Roy J. A1 - Chtourou, Hamdi T1 - Effects of Ramadan observance on dietary intake and body composition of adolescent athletes: systematic review and meta-analysis JF - Nutrients N2 - To evaluate the effects of Ramadan observance on dietary intake, body mass and body composition of adolescent athletes (design: systematic review and meta-analysis; data sources: PubMed and Web of Science; eligibility criteria for selecting studies: single-group, pre-post, with or without control-group studies, conducted in athletes aged <19 years, training at least 3 times/week, and published in any language before 12 February 2020). Studies assessing body mass and/or body composition and/or dietary intake were deemed eligible. The methodological quality was assessed using ‘QualSyst’. Of the twelve selected articles evaluating body mass and/or body composition, one was of strong quality and eleven were rated as moderate. Ten articles evaluated dietary intake; four were rated as strong and the remaining moderate in quality. Continuation of training during Ramadan did not change body mass from before to the first week (trivial effect size (ES) = −0.011, p = 0.899) or from before to the fourth week of Ramadan (trivial ES = 0.069, p = 0.277). Additionally, Ramadan observance did not change body fat content from before to the first week (trivial ES = −0.005, p = 0.947) and from before to the fourth week of Ramadan (trivial ES = -0.057, p = 0.947). Lean body mass remained unchanged from before to the fourth week of Ramadan (trivial ES = −0.025, p = 0.876). Dietary data showed the intake of energy (small ES = -0.272, p = 0.182), fat (trivial ES = 0.044, p = 0.842), protein (trivial ES = 0.069, p = 0.720), carbohydrate (trivial ES = 0.075, p = 0.606) and water (trivial ES = −0.115, p = 0.624) remained essentially unchanged during as compared to before Ramadan. Continued training of adolescent athletes at least three times/week during Ramadan observance has no effect on body mass, body composition or dietary intake. KW - athletes KW - adolescent KW - energy intake KW - fat mass KW - lean mass KW - Ramadan KW - systematic review and meta-analysis Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-205856 SN - 2072-6643 VL - 12 IS - 6 ER - TY - JOUR A1 - Düking, Peter A1 - Achtzehn, Silvia A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Integrated framework of load monitoring by a combination of smartphone applications, wearables and point-of-care testing provides feedback that allows individual responsive adjustments to activities of daily living JF - Sensors N2 - Athletes schedule their training and recovery in periods, often utilizing a pre-defined strategy. To avoid underperformance and/or compromised health, the external load during training should take into account the individual’s physiological and perceptual responses. No single variable provides an adequate basis for planning, but continuous monitoring of a combination of several indicators of internal and external load during training, recovery and off-training as well may allow individual responsive adjustments of a training program in an effective manner. From a practical perspective, including that of coaches, monitoring of potential changes in health and performance should ideally be valid, reliable and sensitive, as well as time-efficient, easily applicable, non-fatiguing and as non-invasive as possible. Accordingly, smartphone applications, wearable sensors and point-of-care testing appear to offer a suitable monitoring framework allowing responsive adjustments to exercise prescription. Here, we outline 24-h monitoring of selected parameters by these technologies that (i) allows responsive adjustments of exercise programs, (ii) enhances performance and/or (iii) reduces the risk for overuse, injury and/or illness. KW - biofeedback KW - eHealth KW - individualized training KW - injury prevention KW - IoT KW - periodization KW - load management Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176506 VL - 18 IS - 5 ER - TY - JOUR A1 - Sperlich, Billy A1 - Achtzehn, Silvia A1 - de Marées, Markus A1 - von Papen, Henning A1 - Mester, Joachim T1 - Load management in elite German distance runners during 3-weeks of high-altitude training JF - Physiological Reports N2 - There is a debate on the optimal way of monitoring training loads in elite endurance athletes especially during altitude training camps. In this case report, including nine members of the German national middle distance running team, we describe a practical approach to monitor the psychobiological stress markers during 21 days of altitude training (~2100 m above sea‐level) to estimate the training load and to control muscle damage, fatigue, and/or chronic overreaching. Daily examination included: oxygen saturation of hemoglobin, resting heart rate, body mass, body and sleep perception, capillary blood concentration of creatine kinase. Every other day, venous serum concentration of blood urea nitrogen, venous blood concentration of hemoglobin, hematocrit, red and white blood cell were measured. If two or more of the above‐mentioned stress markers were beyond or beneath the athlete's normal individual range, the training load of the subsequent training session was reduced. Running speed at 3 mmol L\(^{−1}\) blood lactate (V\(_{3}\)) improved and no athlete showed any signs of underperformance, chronic muscle damage, decrease body and sleep perception as well as activated inflammatory process during the 21 days. The dense screening of biomarkers in the present case study may stimulate further research to identify candidate markers for load monitoring in elite middle‐ and long‐distance runners during a training camp at altitude. KW - distance running KW - training load KW - stress markers KW - biomarkers KW - high-altitude training Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171294 VL - 4 IS - 12 ER - TY - JOUR A1 - Born, Dennis‐Peter A1 - Kunz, Philipp A1 - Sperlich, Billy T1 - Reliability and validity of an agility‐like incremental exercise test with multidirectional change‐of‐direction movements in response to a visual stimulus JF - Physiological Reports N2 - The aim of the study was to evaluate the reliability and validity of cardiorespiratory and metabolic variables, that is, peak oxygen uptake (V'O\(_{2peak}\)) and heart rate (HR\(_{peak}\)), obtained from an agility‐like incremental exercise test for team sport athletes. To investigate the test–retest reliability, 25 team sport athletes (age: 22 ± 3 years, body mass: 75 ± 7 kg, height: 182 ± 6 cm) performed an agility‐like incremental exercise test on the SpeedCourt (SC) system incorporating multidirectional change‐of‐direction (COD) movements twice. For each step of the incremental SC test, the athletes covered a 40‐m distance interspersed with a 10‐sec rest period. Each 40 m distance was split into short sprints (2.25–6.36 m) separated by multidirectional COD movements (0°–180°), which were performed in response to an external visual stimulus. All performance and physiological data were validated with variables obtained from a ramp‐like treadmill and Yo‐Yo intermittent recovery level 2 test (Yo‐Yo IR2). The incremental SC test revealed high test–retest reliability for the time to exhaustion (ICC = 0.85, typical error [TE] = 0.44, and CV% = 3.88), V'O\(_{2peak}\), HR\(_{peak}\), ventilation, and breathing frequency (ICC = 0.84, 0.72, 0.89, 0.77, respectively). The time to exhaustion (r = 0.50, 0.74) of the incremental SC test as well as the peak values for V'O\(_{2}\) (r = 0.59, 0.52), HR (r = 0.75, 0.78), ventilation (r = 0.57, 0.57), and breathing frequency (r = 0.68, 0.68) were significantly correlated (P ≤ 0.01) with the ramp‐like treadmill test and the Yo‐Yo IR2, respectively. The incremental SC test represents a reliable and valid method to assess peak values for V'O\(_{2}\) and HR with respect to the specific demand of team sport match play by incorporating multidirectional COD movements, decision making, and cognitive components. KW - speed KW - Yo‐Yo intermittent recovery KW - change‐of‐direction movement KW - repeated sprint ability KW - team sport Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158265 VL - 5 IS - 9 ER - TY - JOUR A1 - Düking, Peter A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Instant Biofeedback Provided by Wearable Sensor Technology Can Help to Optimize Exercise and Prevent Injury and Overuse JF - Frontiers in Physiology KW - sports KW - training optimization KW - performance monitoring KW - health monitoring KW - technology KW - coaching Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158044 VL - 8 IS - 167 ER - TY - JOUR A1 - Born, Dennis-Peter A1 - Zinner, Christoph A1 - Sperlich, Billy T1 - The mucosal immune function is not compromised during a period of high-intensity interval training. Is it time to reconsider an old assumption? JF - Frontiers in Physiology N2 - Purpose: The aim of the study was to evaluate the mucosal immune function and circadian variation of salivary cortisol, Immunoglobin-A (sIgA) secretion rate and mood during a period of high-intensity interval training (HIIT) compared to long-slow distance training (LSD). Methods: Recreational male runners (n = 28) completed nine sessions of either HIIT or LSD within 3 weeks. The HIIT involved 4 × 4 min of running at 90–95% of maximum heart rate interspersed with 3 min of active recovery while the LSD comprised of continuous running at 70–75% of maximum heart rate for 60–80 min. The psycho-immunological stress-response was investigated with a full daily profile of salivary cortisol and immunoglobin-A (sIgA) secretion rate along with the mood state on a baseline day, the first and last day of training and at follow-up 4 days after the last day of training. Before and after the training period, each athlete's running performance and peak oxygen uptake (V·O\(_{2peak}\)) was determined with an incremental exercise test. Results: The HIIT resulted in a longer time-to-exhaustion (P = 0.02) and increased V·O\(_{2peak}\) compared to LSD (P = 0.01). The circadian variation of sIgA secretion rate showed highest values in the morning immediately after waking up followed by a decrease throughout the day in both groups (P < 0.05). With HIIT, the wake-up response of sIgA secretion rate was higher on the last day of training (P < 0.01) as well as the area under the curve (AUC\(_{G}\)) higher on the first and last day of training and follow-up compared to the LSD (P = 0.01). Also the AUC\(_{G}\) for the sIgA secretion rate correlated with the increase in V·O\(_{2peak}\) and running performance. The AUC\(_{G}\) for cortisol remained unaffected on the first and last day of training but increased on the follow-up day with both, HIIT and LSD (P < 0.01). Conclusion: The increased sIgA secretion rate with the HIIT indicates no compromised mucosal immune function compared to LSD and shows the functional adaptation of the mucosal immune system in response to the increased stress and training load of nine sessions of HIIT. KW - high-volume training KW - periodization KW - circadian rhythm KW - cortisol KW - diurnal profile KW - endurance KW - immunoglobin-A Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158025 VL - 8 IS - 485 ER - TY - JOUR A1 - Zinner, Christoph A1 - Born, Dennis-Peter A1 - Sperlich, Billy T1 - Ischemic preconditioning does not alter performance in multidirectional high-intensity intermittent exercise JF - Frontiers in Physiology N2 - Purpose: Research dealing with ischemic preconditioning (IPC) has primarily focused on variables associated to endurance performance with little research about the acute responses of IPC on repeated multidirectional running sprint performance. Here we aimed to investigate the effects of IPC of the arms and the legs on repeated running sprint performance with changes-of-direction (COD) movements. Methods: Thirteen moderately-to-well-trained team-sport athletes (7 males; 6 females; age: 24 ± 2 years, size: 175 ± 8 cm, body mass: 67.9 ± 8.1 kg) performed 16 × 30 m all-out sprints (15 s rest) with multidirectional COD movements on a Speedcourt\(^{©}\) with IPC (3 × 5 min) of the legs (IPC\(_{leg}\); 240 mm Hg) or of the arms (remote IPC: IPC\(_{remote}\); 180–190 mm Hg) 45 min before the sprints and a control trial (CON; 20 mm Hg). Results: The mean (±SD) time for the 16 × 30 m multidirectional COD sprints was similar between IPC\(_{leg}\) (Mean t: 16.0 ± 1.8 s), IPC\(_{remote}\) (16.2 ± 1.7 s), and CON (16.0 ± 1.6 s; p = 0.50). No statistical differences in oxygen uptake (mean difference: 0%), heart rate (1.1%) nor muscle oxygen saturation of the vastus lateralis (4.7%) and biceps brachii (7.8%) between the three conditions were evident (all p > 0.05). Conclusions: IPC (3 × 5 min) of the legs (220 mm Hg) or arms (180–190 mm Hg; remote IPC) applied 45 min before 16 × 30 m repeated multidirectional running sprint exercise does not improve sprint performance, oxygen uptake, heart rate nor muscle oxygen saturation of the vastus lateralis muscle when compared to a control trial. KW - team sport KW - agility KW - change of direction KW - muscle oxygen saturation KW - near-infrared spectroscopy Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159348 VL - 8 ER - TY - JOUR A1 - Düking, Peter A1 - Zinner, Christoph A1 - Reed, Jennifer L. A1 - Holmberg, Hans‐Christer A1 - Sperlich, Billy T1 - Predefined vs data‐guided training prescription based on autonomic nervous system variation: A systematic review JF - Scandinavian Journal of Medicine & Science in Sports N2 - Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre‐ and post‐intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV‐based interventions reduced the amount of moderate‐ and/or high‐intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV‐based training. Peak oxygen uptake (VO\(_{2peak}\)) and submaximal running parameters (eg, LT1, LT2) improved following both HRV‐based and predefined training, with no clear difference in the extent of improvement in VO\(_{2peak}\). Submaximal running parameters tended to improve more following HRV‐based training. Research findings to date have been limited and inconsistent. Both HRV‐based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater. KW - cardiorespiratory fitness KW - eHealth KW - endurance KW - innovation KW - technology KW - training KW - wearable Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-217893 VL - 30 IS - 12 SP - 2291 EP - 2304 ER - TY - JOUR A1 - Düking, Peter A1 - Fuss, Franz Konstantin A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - Recommendations for assessment of the reliability, sensitivity, and validity of data provided by wearable sensors designed for monitoring physical activity JF - JMIR Mhealth and Uhealth N2 - Although it is becoming increasingly popular to monitor parameters related to training, recovery, and health with wearable sensor technology (wearables), scientific evaluation of the reliability, sensitivity, and validity of such data is limited and, where available, has involved a wide variety of approaches. To improve the trustworthiness of data collected by wearables and facilitate comparisons, we have outlined recommendations for standardized evaluation. We discuss the wearable devices themselves, as well as experimental and statistical considerations. Adherence to these recommendations should be beneficial not only for the individual, but also for regulatory organizations and insurance companies. KW - internet of things KW - activity tracker KW - data mining KW - load management KW - physical activity KW - smartwatch Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176202 VL - 6 IS - 4 ER - TY - JOUR A1 - Düking, Peter A1 - Holmberg, Hans-Christer A1 - Sperlich, Billy T1 - The potential usefulness of virtual reality systems for athletes: a short SWOT analysis JF - Frontiers in Physiology N2 - No abstract available. KW - SWOT KW - virtual reality KW - athletes Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176178 VL - 9 IS - 128 ER - TY - JOUR A1 - Sperlich, Billy A1 - Holmberg, Hans-Christer T1 - The responses of elite athletes to exercise: an all-day, 24-h integrative view is required! JF - Frontiers in Physiology N2 - No abstract available. KW - physiological KW - athletes KW - wearable sensors KW - training intensity distribution KW - monitoring KW - biofeedback Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158655 VL - 8 IS - 564 ER - TY - JOUR A1 - Sperlich, Billy A1 - Düking, Peter A1 - Holmberg, Hans-Christer T1 - A SWOT analysis of the use and potential misuse of implantable monitoring devices by athletes JF - Frontiers in Physiology N2 - Kein Abstract vorhanden. KW - ingestible sensor KW - sensor assessment KW - implant KW - implantable neurostimulators KW - athletes Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158742 VL - 8 IS - 629 ER -