Purpose
: We compared the adaptive responses to supramaximal high-intensity interval training (HIIT) individualized according to anaerobic speed reserve (ASR), the 30-15 Intermittent Fitness Test (V
IFT), and velocity associated with maximum oxygen uptake (MAS) to determine which approach facilitates more identical adaptations across athletes with different profiles.
Methods
: Thirty national-level basketball players (age = 28.4 [5] y; body mass = 88.9 [6.3] kg; height = 190 [4.8] cm) were randomly assigned to 3 training groups performing 2 sets of 4, 6, 8, 6, 8, and 10-minute runs (from first to sixth week, respectively), consisting of 15-second running at Δ%20ASR (MAS + 0.2 × ASR), 95%V
IFT, and 120%MAS, with 15 seconds recovery between efforts and a 3-minute relief between sets.
Results
: All 3 interval interventions significantly (P < .05) enhanced maximum oxygen uptake (
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Individualizing Basketball-Specific Interval Training Using Anaerobic Speed Reserve: Effects on Physiological and Hormonal Adaptations
Chenhang Wang and Mingliang Ye
Why Should Athletes Brake Fast? Influence of Eccentric Velocity on Concentric Performance During Countermovement Jumps at Different Loads
Jose L. Hernández-Davó, Rafael Sabido, Manuel Omar-García, and Daniel Boullosa
Purpose: The aim of the present study was to analyze the effect of different eccentric tempos on eccentric kinetics and kinematics and the subsequent concentric performance when performing countermovement jumps against different loads. Methods: After 1-repetition-maximum assessment and 2 familiarization sessions, 13 well-trained participants performed, in randomized order, 12 sets (4 tempos × 3 loads) of 4 repetitions of the loaded countermovement-jump exercise. The eccentric tempos analyzed were 5 and 2 seconds, as fast as possible, and accelerated (ie, without pause between repetitions), while the loads used were 30%, 50%, and 70% of 1-repetition maximum. Several kinetic and kinematic variables during both phases were recorded by linking a linear position transducer to the barbell. Results: The eccentric work was greater in the accelerated condition despite no changes in the eccentric depth. The peak and mean propulsive velocities were greater in the as-fast-as-possible and accelerated conditions. Correlation analysis showed that, compared with the 5-second condition, the increased concentric performance in the accelerated condition was related to the difference in eccentric work performed in the last 100 milliseconds of the eccentric phase (r > .770). Conclusions: Contrary to current practices, the current study highlights the need for performing the eccentric phase of loaded countermovement jumps, a common exercise performed by athletes for both training and evaluation purposes, as fast as possible. This allows not only a greater eccentric work but also improved concentric performance.
Effects of High-Intensity Inspiratory Muscle Warm-Up on High-Intensity Exercise Performance and Muscle Oxygenation
Jun Koizumi and Toshiyuki Ohya
Purpose: An inspiratory muscle warm-up (IMW) improves inspiratory muscle function, but the effects of high-intensity exercise are inconsistent. We aimed to determine the effects of high-intensity IMW on high-intensity exercise performance and muscle oxygenation.
Methods: Ten healthy men (maximal oxygen uptake [
Effects of Hypoxia Severity on Muscle Oxygenation Kinetics Using Statistical Parametric Mapping During Repeated Treadmill Sprints
Clint Hansen, Franck Brocherie, Grégoire P. Millet, and Olivier Girard
Purpose: We examined the effects of increasing hypoxia severity on oxygenation kinetics in the vastus lateralis muscle during repeated treadmill sprints, using statistical parametric mapping (SPM). Methods: Ten physically active males completed 8 sprints of 5 seconds each (recovery = 25 s) on a motorized sprint treadmill in normoxia (sea level; inspired oxygen fraction = 0.21), moderate hypoxia (inspired oxygen fraction = 0.17), and severe hypoxia (SH; inspired oxygen fraction = 0.13). Continuous assessment of tissue saturation index (TSI) in the vastus lateralis muscle was conducted using near-infrared spectroscopy. Subsequently, TSI data were averaged for the sprint–recovery cycle of all sprints and compared between conditions. Results: The SPM analysis revealed no discernible difference in TSI signal amplitude between conditions during the actual 5-second sprint phase. However, during the latter portion of the 25-second recovery phase, TSI values were lower in SH compared with both sea level (from 22 to 30 s; P = .003) and moderate hypoxia (from 16 to 30 s; P = .001). The mean distance covered at sea level (22.9 [1.0] m) was greater than for both moderate hypoxia (22.5 [1.2] m; P = .045) and SH (22.3 [1.4] m; P = .043). Conclusions: The application of SPM demonstrated that only SH reduced muscle oxygenation levels during the late portion of the passive (recovery) phase and not the active (sprint) phase during repeated treadmill sprints. These findings underscore the usefulness of SPM for assessing muscle oxygenation differences due to hypoxic exposure and the importance of the duration of the between-sprints recovery period.
Training Regimen of an Elite Ultramarathon Runner: A Case Study of What Led Up to the 24-Hour World-Record Run
Jonathan Byrne, Sarah Lynch, and G. Monique Mokha
Purpose: Ultramarathon running has gained popularity over several decades. Although there has been considerable research on training for other running events, from the 100-m to the marathon at 26.2 miles (42.2 km), there is little evidence on best practices for ultramarathons, where distances potentially exceed 100 miles (160.9 km). Methods: In this case study, we examine the training regimen of an elite ultramarathon runner who broke 8 world records in 2021 and 2022, including the 24-hour run in which he ran 319.6 km in September 2022. Training data from December 28, 2020, to September 17, 2022, were collected from the Strava application database (recorded on Coros watch) and analyzed using Microsoft Excel and Tableau. Results: Our subject completed 5 training blocks, with volume per training block averaging 172.1 to 263 km/wk. Peak running volume per training block occurred on average 3.2 weeks out from races and reached a maximum of 378 km/wk. Recovery was emphasized the week following a race, with less running (19 km/wk) and more cross-training. Interval-type workouts (1- to 10-km repeats) were completed throughout training blocks. The average pace during the 24-hour world-record run was 4 minutes and 30 seconds per kilometer (4:30/km), closely matching the overall average training pace. Conclusions: These findings suggest that training for ultramarathon races should include high-volume running at varied paces and intensity with cross-training to avoid injuries. We hope that this evidence helps athletes understand how to prepare for these ultraendurance events.
The Dose–Response in Elite Soccer: Preliminary Insights From Menstrual-Cycle Tracking During the FIFA Women’s World Cup 2019
Dawn Scott, Georgie Bruinvels, Dean Norris, and Ric Lovell
Purpose: This preliminary study examined the influence of estimated menstrual-cycle (MC) phase on responses to soccer matches and training sessions in preparation for and during the FIFA (Fédération internationale de football association) Women’s World Cup 2019. Methods: Twenty outfield players representing a national team were tracked over a 45-day period. External (10-Hz global positioning system; total and distance covered at high-metabolic power [≥20 W·kg−1]) and internal load measures (minutes ≥80% heart-rate maximum, sessional ratings of perceived exertion) were collected during all training and matches, with single-item wellness measures (fatigue, soreness, sleep quality, and sleep duration) collected each morning prior to activity. MC phase was estimated individually via an algorithm, informed from pretournament survey responses and ongoing symptom reporting (FitrWoman). Model comparison statistics were used to determine the impact of estimated MC phase in nonhormonal contraceptive users (n = 16). Results: Sessional rating of perceived exertion responses to total distances ≥5 km were higher during the luteal phase (+0.6–1.0 au; P ≤ .0178) versus menstruation (phase 1), but no other observable dose–response trends were observed. Sleep, fatigue, and soreness ratings were not typically associated with MC phase, with the exception of exacerbated fatigue ratings in luteal versus follicular phase 48 hours postmatch (−0.73 au, P = .0275). Conclusions: Preliminary findings suggest that estimated MC phase may contribute to the understanding of the dose–response to soccer training and matches.
Variability of External Load Measures During Soccer Match Play: Influence of Player Fitness or Pacing?
Alireza Rabbani, Giorgios Ermidis, Filipe Manuel Clemente, and Craig Twist
Purpose: The aims of this study were to examine the variability of selected external load metrics within 15-minute intervals during soccer match play and examine their relationship with players’ high-intensity intermittent fitness. Methods: A total of 18 male soccer players were monitored for their external load metrics during 26 matches, which included total distance, high-metabolic-load distance, and mechanical work (defined as the sum of accelerations and decelerations >3 m2). Additionally, players completed the 30-15 Intermittent Fitness Test. Results: Total distance had lower coefficients of variation than high-metabolic-load distance and mechanical work (effect size [ES]: 5.2 to 6.4; very large). Within-player Δ-15min showed moderate to large decreases (ES: −0.7 to −1.6) and increases (ES: 0.9 to 1.8) in absolute and coefficient-of-variation values, respectively. Large relationships (r = .55 to .61) were observed between the Intermittent Fitness Test and 15-minmean and 15-minbest in all selected external load metrics. However, small to moderate (0.27 to 0.41) associations were observed between the Intermittent Fitness Test and Δ-15min in selected external load metrics. Conclusions: These findings suggest that players with relatively lower intermittent running capacity might show lower variability during matches, as evidenced by smaller reductions in high-intensity actions during the final 15 minutes. We attribute these observations to players’ possessing better pacing strategies.
Effect of the Fran CrossFit Workout on Oxygen Uptake Kinetics, Energetics, and Postexercise Muscle Function in Trained CrossFitters
Manoel Rios, Klaus Magno Becker, Ana Sofia Monteiro, Pedro Fonseca, David B. Pyne, Victor Machado Reis, Daniel Moreira-Gonçalves, and Ricardo J. Fernandes
Purpose: Fran is one of the most popular CrossFit benchmark workouts used to control CrossFitters’ improvements. Detailed physiological characterization of Fran is needed for a more specific evaluation of CrossFitters’ training performance improvements. The aim of the study was to analyze the oxygen uptake (
Effect of Wetsuit Use on Body Temperature and Swimming Performance During Training in the Pool: Recommendations for Open-Water Swimming Training With Wetsuits
Tomomi Fujimoto, Yuiko Matsuura, Yasuhiro Baba, and Reira Hara
Purpose: Open-water swimmers need to train with wetsuits to get familiar with them; however, body core temperature (T core) kinetics when using wetsuits in swimming-pool training remains unclear. The present study assessed the effects of wetsuit use in pool training on T core, subjective perceptions, and swimming performance to obtain suggestions for wearing wetsuits in training situations. Methods: Four elite/international-level Japanese swimmers (2 female, age 24 [1] y) completed two 10-km trials with (WS) and without wetsuit (SS) in the swimming pool (T w: 29.0 °C). During the trial, swimmers were allowed to remove their wetsuit if they could no longer tolerate the heat. T core was continuously recorded via ingestible temperature sensors. Swimming speed was estimated from every 100-m lap time. Results: T core increased by distance in both trials in all swimmers. T core when swimmers removed their wetsuit in the WS (distance: 3800 [245] m, time: 2744 [247] s) was higher than that at the same distance in the SS in all swimmers. Rating of perceived exertion was higher in the SS than the WS, and swimming speed was slower in the WS than the SS in all swimmers. Conclusion: Wetsuit use during pool training increases T core and decreases swimming performance. Although wearing wetsuits in training situations is important for familiarization, for the safety of the swimmers, it is recommended that they remove their wetsuit if they feel too hot.
Acute Responses to Repeated-Sprint Training in Hypoxia Combined With Whole-Body Cryotherapy: A Preliminary Study
Thibaud Mihailovic, Alain Groslambert, Romain Bouzigon, Simon Feaud, Grégoire P. Millet, and Philippe Gimenez
Purpose: This study aimed to investigate acute psychophysiological responses to repeated-sprint training in hypoxia (RSH) combined with whole-body cryotherapy (WBC). Method: Sixteen trained cyclists performed 3 sessions in randomized order: RSH, WBC-RSH (WBC pre-RSH), and RSH-WBC (WBC post-RSH). RSH consisted of 3 sets of 5 × 10-second sprints with 20-second recovery at a simulated altitude of 3000 m. Power output, muscle oxygenation (tissue saturation index), heart-rate variability, and recovery perception were analyzed. Sleep quality was assessed on the nights following test sessions and compared with a control night using nocturnal ActiGraphy and heart-rate variability. Results: Power output did not differ between the conditions (P = .27), while the decrease in tissue saturation index was reduced for WBC-RSH compared to RSH-WBC in the last set. In both conditions with WBC, the recovery perception was higher compared to RSH (WBC-RSH: +15.4%, and RSH-WBC: +21.9%, P < .05). The number of movements during the RSH-WBC night was significantly lower than for the control night (−18.7%, P < .01) and WBC-RSH (−14.9%, P < .05). RSH led to a higher root mean square of the successive differences of R-R intervals and high-frequency band during the first hour of sleep compared to the control night (P < .05) and RSH-WBC (P < .01). Conclusions: Inclusion of WBC in an RSH session did not modify the power output but could improve prolonged performance in hypoxia by maintaining muscle oxygenation. A single RSH session did not deteriorate sleep quality. WBC, particularly when performed after RSH, positively influenced recovery perception and sleep.