Effects of normobaric hypoxia on upper body critical power and anaerobic working capacity

Abstract

PurposeTo evaluate the effects of moderate normobaric hypoxia on the parameters of the work-time relationship in the upper body. MethodsTwenty-one recreationally active men completed a graded exercise test in both normobaric hypoxia (H) and normoxia (N) to exhaustion on an arm ergometer to determine V̇O2peak and peak power output (PPO). Each participant completed four constant work-rate (CWR) arm-cranking tests at 90–120% PPO in both environmental conditions. Linear regression was used to estimate critical power (CP) and anaerobic working capacity (AWC) via work-time relationship during the CWR tests. ResultsH significantly reduced V̇O2peak (N: 2.34 ± 0.34 L vs. H: 2.27 ± 0.34 L, p = 0.041), PPO (N: 125.29 ± 17.98 W vs. H: 121.11 ± 17.98 W, p = 0.001), and CP (N: 90.22 ± 12.88 W vs. H: 85.26 ± 9.64 W, p = 0.042), but had no effect on AWC (N: 9.16 ± 2.81 kJ vs. H: 8.75 ± 3.23 kJ, p = 0.600). DiscussionModerate normobaric hypoxia appears to reduce CP in the upper body but has a variable effect on AWC.