Sex-Specific Effect on Accumulated Oxygen Deficit During Short and Middle-Distance Swimming Performance

This study assessed the accumulated oxygen deficit (AOD) during 50, 100, and 200 m front-crawl performances to compare the responses between sexes and analyse the effect of lean body mass (LBM). Twenty swimmers (16.2 ± 2.8 years, 61.6 ± 7.8 kg, and 48.8±11.2 kg LBM) performed 50, 100, and 200 m to determine accumulated oxygen uptake (V̇O 2Ac ). The swimmers also performed an incremental test from which five submaximal steps were selected to estimate the oxygen demand (V̇O 2demand ) from the V̇O 2 vs velocity adjustment. V̇O 2 was sampled using a gas analyser coupled with a respiratory snorkel. AOD was the difference between V̇O 2demand and V̇O 2Ac , and LBM was assessed by dual-energy absorptiometry. A two-way ANOVA evidenced an AOD increase with distance for both sexes: 19.7 ± 2.5 vs 24.9 ± 5.5, 29.8 ± 8.0 vs 36.5 ± 5.8, and 41.5 ± 9.4 vs 55.2 ± 11.9 ml×kg −1 , respectively for 50, 100, and 200 m (with highest values for females, P < 0.01). Inverse correlations were observed between LBM and AOD for 50, 100, and 200 m (r = -0.60, -0.38 and − 0.49, P < 0.05). AOD increased from 50 to 200 m distances for both sexes. However, females presented higher AOD values, which probably relates to the effect of reduced LBM on increasing the rate of oxygen deficit (i.e., anaerobic energy demand).