Changes in Cycling Efficiency during a Competitive Season

Abstract

To monitor training-related changes in gross efficiency (GE) over the course of a competitive cycling season. Fourteen trained cyclists (mean +/- SD: 34 + 8 yr, 74.3 +/- 7.4 kg, Wmax = 406 +/- 43 W, V O2max = 59.5 +/- 3.8 mL x kg x min) with at least 3 yr competitive experience completed five laboratory tests during a competitive cycling season. The tests measured lactate threshold (LT), onset of blood lactate accumulation (OBLA), maximal oxygen uptake (V O2max), maximal minute power (Wmax), and GE. The data were analyzed using repeated-measures ANOVA and Pearson's product-moment correlation coefficient. GE changed significantly over the course of the competitive cycling season (P < 0.05), increasing over the precompetition phase of the season (19.6% vs 20.6%; P < 0.05). GE was maintained during the main competitive phase of the season (20.6% vs 20.3%; P > 0.05) and then decreased during the postcompetitive phase to 19.4% (P < 0.05). The precompetition changes in GE were related to the total time spent training and the time spent above OBLA intensity (r = 0.84 and 0.80, respectively). Riders who spent the most time training between LT and OBLA intensities (r = 0.87; P < 0.05) were better able to maintain GE. A significant inverse relationship was also identified between the changes in GE and the percentage change in training below LT over the competitive phase of the season. GE changes over the course of a competitive cycling season and is related to the volume and intensity of training conducted.