2016, Vol. 3, Issue 3, Part C

Materials and Methods: Twelve physically active males (24 ± 3 years, 178 ± 6 centimetres (cm), 82.5 ± 12.2 kilograms (kg)) volunteered to complete two 5x6s tests. An electronically braked cycle ergometer was used, with a fly wheel braking force corresponding to 5% and 7.5% bodyweight being used for the upper and lower body 5x6s respectively. The 5x6s consisted of 5 maximal sprints, 6 seconds (s) in duration, separated by 24 s of passive recovery. Body composition was assessed via dual energy x-ray absorptiometry. A one-way repeated measures analysis of variance determined significance differences between the upper and lower body sprint performances. 

Results: Peak power was found to be significantly (P<0.05) greater for the lower body for all sprints even when expressed relative to bodyweight (W•kg-1) (P<0.01 sprint 1-4, P<0.05 sprint 5), lean body mass (W•kg-1 LBM) (P<0.01 sprint 1-4, P<0.05 sprint 5) and active muscle mass (W•kg-1 AMM) (P<0.001 sprint 1-5). There was a significant (P<0.05) difference in both percentage decrement in total work and peak power fatigue index (FIp) over the 5 sprints between the upper body and lower body. 

Conclusions: The lower body is more powerful than the upper body, even when expressed relative to active muscle mass, with the upper body having a greater decrement in total work and a higher peak power fatigue index compared to the lower body performance.