Effect of cadence, cycling experience, and aerobic power on delta efficiency during cycling

Purpose: To examine the influence of cadence, cycling experience, and aerob ic power on delta efficiency during cycling and to determine the significan ce of delta efficiency as a factor underlying the selection of preferred ca dence, Methods: Delta efficiency (DE) was determined for ii trained experie nced cyclists (C), 10 trained runners (R), and 10 less-trained noncyclists (LT) at 50, 65, 80, 95, and 110 rpm. Preferred cadence (PC) was determined at 100, 150, and 200 W for C and R and at 75, 100, and 150 W for LT. Gas ex change at each power output (PO) was measured on a separate day, and the fi ve cadences were randomly ordered on each occasion. It was hypothesized tha t: a) cyclists are most efficient at the higher cadences at which they are accustomed to training and racing, i.e., there will be a trend for DE to in crease with increases in cadence; b) cyclists and runners will exhibit simi lar DE across the range of cadences tested; and c) DE of less-trained subje cts will be lower than that of cyclists and runners. Results: PCs of C and R were similar and did not change appreciably with PO (100 W: C, 95.6 +/- 1 0.8, R, 92.0 +/- 8.5: 150 W: C, 94.4 +/- 10.3; R, 92.9 +/- 7.8: 200 W: C, 9 2.2 +/- 7.2; R, 91.8 +/- 7.9 rpm). The PC of LT was significantly lower and decreased with increases in power output (75 W: 80.0 +/- 15.3; 100 W: 77.5 +/- 15.1; 150 W: 69.1 +/- 11.9 rpm). The first hypothesis was rejected bec ause analysis of the cyclists' data alone revealed no systematic increase i n DE as cadence was increased [F(4, 40) = 0.272, P = 0.894]. Repeated measu res ANOVA an all three groups revealed no group X cadence interaction [F(8, 112) = 0.589, P = 0.785]. Again there was no systematic Effect of cadence o n DE [F(4.112) = 1.058, P = 0.381]. The second and third hypotheses were al so rejected since there was no group main effect, i.e., DE of cyclists, run ners, and less-trained subjects were not significantly different [F(2,28) = 1.397, P = 0.264]. Conclusion: Pedaling cadence did not have a dramatic ef fect on DE in any group. Muscular efficiency, as measured indirectly by del ta efficiency, appears to remain relatively constant at approximately 24%, regardless of cycling experience or fitness level.