Abstract
The aim of this study was to investigate the effect of a 4 weeks in-water swimming-specific repeated-sprint training in hypoxia (RSH) compared to similar training in normoxia (RSN). Following a repeated-measures, counterbalanced cross-over design, 10 swimmers were requested to perform two trials consisting of in-water repeated sprints in hypoxic (RSH, simulated 4,040 m; FiO2 = 13.7%) or normoxic (RSN, 459 m, FiO2 calibrated = 20.9%) conditions. In both conditions, 8 additional exercise including 3 sets of 5 × 15 m “all-out” sprints (corresponding to a total of 625 m), with 20 s of passive recovery between efforts and 200 m of easy swimming between sets were included at the end of their swimming program over a 4 weeks period. Hypoxic condition was generated using a simulator pumping air with lowered oxygen concentration into a facial mask. An incremental maximal test on an ergocycle, as well as 100 m and 400 m freestyle swimming performance (real competition format) were assessed before (pre), 7 days (post-1), and 2 weeks (post-2) after intervention. During training, heart rate (HR) and oxygen saturation (SpO2) were monitored. RSH showed significantly lower SpO2 (70.1 ± 4.8% vs. 96.1 ± 2.7%, P < 0.01), concomitant with higher mean HR (159 ± 11 bmp vs. 141 ± 6 bmp, P < 0.01) than RSN. No significant changes in maximal oxygen uptake, other submaximal physiological parameters, 100 or 400 m swimming performances were found. Although providing additional physiological stress, performing in-water RSH does not provide evidence for higher benefits than RSN to improve swimmers performance.
Highlights
Live low-train high (LLTH) is a popular hypoxic training approach, for the simple reason that it does not disturb athletes’ usual training routine (Girard et al, 2020)
Findings indicate that a 4 weeks repeated-sprint training in hypoxia (RSH) period (i.e., 8 additional sessions, 3 sets of 5 × 15 m “all-out” sprint, 20 s active recovery between sprint, 200 m of easy swimming between sets performed at a 4,040 m, FiO2 13.7 ± 0.3%) did not elicit higher 100 and 400 m freestyle swimming performance, despite higher physiological stress during training compared with RSN
Normobaric hypoxia resulted in larger hypoxemia during RSH, which would increase the demand on anaerobic pathway to maintain ATP provision rate (Girard et al, 2017)
Summary
Live low-train high (LLTH) is a popular hypoxic training approach, for the simple reason that it does not disturb athletes’ usual training routine (Girard et al, 2020). Few studies have investigated the effects of such LLTH methods on swimmers performance. To the best of the authors knowledge, dryland-based intermittent hypoxic training (IHT) (Czuba et al, 2017; Park et al, 2018) and in-water swimming-specific training using voluntary hypoventilation at low-lung volume (VHL) (Woorons et al, 2016; Trincat et al, 2017) or prolonged expiration and reducedfrequency breathing (Toubekis et al, 2017) have been reported. 18 IHT sessions at a simulated altitude of 3,000 m enhanced VO2max and 400 m freestyle performance in moderately trained swimmers (Park et al, 2018). 8 IHT sessions at a simulated altitude of 2,500 m were
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
