No Differences in Gross Efficiency Between Subjects With Varying Aerobic Capacities

The aim of this experiment was to investigate a possible relationship between aerobic capacity (VO2peak) and gross efficiency (GE) during submaximal cycling. 73 subjects with VO2peak values ranging from 45.1 to 83.1 ml.kg−1.min−1 performed an incremental exercise test to exhaustion on a cycle ergometer beginning at 95 W and increasing by 35 W every 3 minutes. Cadence was maintained between 80–90 rpm. Oxygen uptake was averaged over the last two minutes of each stage. Subjects were divided into three groups by VO2peak corresponding to <60 ml.kg−1.min−1 (L, n = 27), 60–70 ml.kg−1.min−1 (M, n = 33) and >70ml.kg−1.min−1 (H, n = 13). GE was averaged for all workloads between 50–70% VO2peak. All data is presented as mean ± SD. Mean VO2peak (ml.kg−1.min−1) was significantly different between the groups (L = 55.3 ± 6.2, M = 63.4 ± 5.7, H = 75.5 ± 9.6, F2,70 = 128.7, p < 0.01). Despite a wide range of aerobic capacities there was no correlation between VO2peak and mean GE (r = 0.156, p = 0.188). One-way ANOVA revealed no significant differences in GE (%) between the groups (L = 18.6 ± 1.0, M = 18.8 ± 1.5, H = 18.9 ± 1.0, F2,70 = 0.322, p = 0.726). These data suggest that aerobic capacity is not related to gross efficiency.