Abstract
BACKGROUND: Studying relative anaerobic and aerobic metabolism contributions to total energy release during exercise may be valuable in understanding exercise energetic demands and the energetic adaptations that occur in response to acute or chronic exercise in obese adults. The aim of the present study is to evaluate the effects of 6 weeks of high-intensity training (HIT) on relative anaerobic and aerobic contributions to total energy release and on peak power output during repeated supramaximal cycling exercises (SCE) in obese adults. METHODS: Twenty-four obese adults (body mass index = ± 33 kg.m(-2)) were randomized into a control group (n = 12) and an HIT group (n = 12). Accumulated oxygen deficits (ml.min(-1)) and anaerobic and aerobic contributions (%) were measured in all groups before and after training via repeated SCE. In addition, the peak power output performed during SCE was determined using the force-velocity test. RESULTS: Before HIT, anaerobic contributions to repeated SCE did not differ between the groups and decreased significantly during the third and fourth repetitions. After HIT, anaerobic contributions increased significantly in the HIT group (+11 %, p < 0.01) and were significantly higher than those of the control group (p < 0.01). Moreover, the peak power obtained during SCE increased significantly in the HIT group (+110 W.kg(-1), p < 0.01) and correlated positively with increases in anaerobic contributions (r = 0.9, p < 0.01). CONCLUSIONS: In obese adults, HIT increased anaerobic contributions to energy release which were associated with peak power enhancement in response to repeated SCE. Consequently, HIT may be an appropriate approach for improving energy contributions and muscle power among obese adults.