Aerobic and anaerobic energy contribution during maximal work output in 90 s determined with various ergocycle workloads.

The aim of this experiment was to evaluate the effect of different workloads on the relative contribution of the various energy delivery systems during a 90-s ergocycle test. Nine male subjects, 22 +/- 1 (mean +/- SD) years of age and weighing 71.4 +/- 6.8 kg, were submitted to a VO2max test, as 10-s test (0.1 kp/kg) and three 90-s tests at different loads (LO: 0.05, ME: 0.075 and HI: 0.1 kp/kg) on an ergocycle. No difference was found between peak power output during the 10-s and HI tests. No differences were observed in the total work output performed during 90 s at different workloads (between 481 and 495 J/kg) as well as in the contribution of aerobic and anaerobic pathways to total energy production. However, VO2max was reached earlier during the ME and HI tests than during the LO test. These results indicate that variation in workload did not influence the total work output and the total contribution of aerobic and anaerobic systems during maximal 90-s ergocycle performances. However, variation in workload had an impact on the relative aerobic and anaerobic contribution at various time points. It is concluded that a 90-s ergocycle test with a resistance of at least 0.1 kp/kg is required to appropriately assess maximal anaerobic power while anaerobic capacity might be measured with workloads as low as 0.05 kp/kg.