TY - JOUR
T1 - Acute performance responses to repeated treadmill sprints in hypoxia with varying inspired oxygen fractions, exercise-to-recovery ratios and recovery modalities
AU - Tong, Tomas K.
AU - Tao, Emma Dan
AU - Chow, Bik C.
AU - Baker, Julien S.
AU - Jiao, Jojo J.
N1 - Funding Information:
The experiments were carried out at Dr. Stephen Hui Research Centre for Physical Recreation and Wellness. The authors wish to thank all the participants for volunteering. The authors also thank Mr. Lee Ho Leung for his assistance in data collection.
Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
PY - 2021/7
Y1 - 2021/7
N2 - Purpose: For optimizing the quality of repeated-sprint training in hypoxia, the differences in the acute performance responses to a single session of repeated-sprint exercise with various (i) inspired oxygen fractions; (ii) exercise-to-recovery (E:R) ratios and (iii) recovery modalities were examined.Methods: Ten male participants performed three sets, 5 × 5-s all-out treadmill sprints, E:R ratio of 1:5, passive recovery, in seven trials randomly. In four of the seven trials, hypoxic levels were set corresponding to sea level (SL1:5P), 1500 (1.5K1:5P), 2500 (2.5K1:5P), and 3500 m (3.5K1:5P), respectively. In a further two trials, the hypoxic level of 3.5K1:5P was maintained, while the E:R ratio was reduced to 1:4 (3.5K1:4P) and 1:3 (3.5K1:3P), respectively. In the last trial, the passive recovery mode of 3.5K1:5P was changed to active (3.5K1:5A).Results: In comparison to SL1:5P, the averaged peak velocity (P-Vel), mean velocity (M-Vel), and velocity decrement score (Sdec) of the sprints, and the cumulative HR-based training impulse (cTRIMP) in 1.5K1:5P and 2.5K1:5P were well maintained. Minor decrement in the M-Vel was found in 3.5K1:5P. Conversely, lowered E:R ratio in 3.5K1:4P and 3.5K1:3P significantly reduced the P-Vel (≥ −2.3%, Cohen’s d ≥ 0.43) and M-Vel (≥ −2.4%, ≥ 0.49), and in 3.5K1:3P altered the Sdec (107%, ≥ 0.96), and cTRIMP (−16%, 1.39), when compared to 3.5K1:5P. Furthermore, mild reductions in M-Vel (−2.6%, 0.5) was observed in 3.5K1:5A using the active recovery mode. Other variables did not change.Conclusion: The findings suggest that a 3.5K1:5P marginally maintained sea-level training loads, and as a result, could maximally optimize the training stress of hypoxia.
AB - Purpose: For optimizing the quality of repeated-sprint training in hypoxia, the differences in the acute performance responses to a single session of repeated-sprint exercise with various (i) inspired oxygen fractions; (ii) exercise-to-recovery (E:R) ratios and (iii) recovery modalities were examined.Methods: Ten male participants performed three sets, 5 × 5-s all-out treadmill sprints, E:R ratio of 1:5, passive recovery, in seven trials randomly. In four of the seven trials, hypoxic levels were set corresponding to sea level (SL1:5P), 1500 (1.5K1:5P), 2500 (2.5K1:5P), and 3500 m (3.5K1:5P), respectively. In a further two trials, the hypoxic level of 3.5K1:5P was maintained, while the E:R ratio was reduced to 1:4 (3.5K1:4P) and 1:3 (3.5K1:3P), respectively. In the last trial, the passive recovery mode of 3.5K1:5P was changed to active (3.5K1:5A).Results: In comparison to SL1:5P, the averaged peak velocity (P-Vel), mean velocity (M-Vel), and velocity decrement score (Sdec) of the sprints, and the cumulative HR-based training impulse (cTRIMP) in 1.5K1:5P and 2.5K1:5P were well maintained. Minor decrement in the M-Vel was found in 3.5K1:5P. Conversely, lowered E:R ratio in 3.5K1:4P and 3.5K1:3P significantly reduced the P-Vel (≥ −2.3%, Cohen’s d ≥ 0.43) and M-Vel (≥ −2.4%, ≥ 0.49), and in 3.5K1:3P altered the Sdec (107%, ≥ 0.96), and cTRIMP (−16%, 1.39), when compared to 3.5K1:5P. Furthermore, mild reductions in M-Vel (−2.6%, 0.5) was observed in 3.5K1:5A using the active recovery mode. Other variables did not change.Conclusion: The findings suggest that a 3.5K1:5P marginally maintained sea-level training loads, and as a result, could maximally optimize the training stress of hypoxia.
KW - Intermittent hypoxic training
KW - Repeated-sprint training in hypoxia
KW - Team sports
KW - Training load
UR - http://www.scopus.com/inward/record.url?scp=85102572831&partnerID=8YFLogxK
U2 - 10.1007/s00421-021-04628-1
DO - 10.1007/s00421-021-04628-1
M3 - Journal article
C2 - 33730209
AN - SCOPUS:85102572831
SN - 1439-6319
VL - 121
SP - 1933
EP - 1942
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
IS - 7
ER -
