The purpose of this study was to compare power outputs, and blood concentrations of lipid hydroperoxides (LH), malondialdehyde (MDA) and lactate ([La-] B) following 30s of maximal cycle ergometry when resistive forces were derived from total-body mass (TBM) or fat-free mass (FFM). Differences (P < 0.05) in peak power output (PPO), pedal velocity (PV) and resistive forces (RF) were observed when the TBM and FFM protocols were compared (953 ± 114 W vs 1020 ± 134 W ; 134 ± 8 rpm vs 141 ± 7 rpm ; 6 ± 1 kg vs 5 ± 1 kg respectively). LH and MDA concentrations increased immediately post exercise during the TBM protocol only (P < 0.05) and decreased 24 h post exercise. Alphatocopherol and uric acid concentrations decreased immediately post exercise for both protocols (P < 0.05) and increased 24 h later (P < 0.05). The results of the study suggest that greater power outputs are obtainable with significantly less oxidative stress when resistive forces reflect FFM as opposed to TBM.