PHYSIOLOGICAL DIFFERENCES BETWEEN PROFESSIONAL AND ELITE ROAD CYCLISTS

The purpose of this study was to compare the physiological responses o f professional and elite road cyclists during an incremental cycle erg ometer test. Twenty-five elite cyclists (EC; 23 +/- 1 yr) and 25 profe ssional cyclists (PC; 25 +/- 2 yr) performed a ramp protocol (increase s of 25 W.min(-1)) during which the following parameters were measured : oxygen consumption ((V) over dot O-2), pulmonary ventilation (VE), v entilatory equivalents for oxygen and carbon dioxide (VE.(V) over dot O-2(-1) and VE.(V) over dot CO2-1, respectively), respiratory exchange ratio (RER), ventilatory thresholds 1 and 2 (VT1 and VT2, respectivel y), blood lactate, and electromyographic activity (EMG) of the vastus lateralis. Significant differences existed between the two groups main ly at submaximal intensities, since both VT, and VT, occurred at a hig her exercise intensity (p < 0.001) in PC than in EC (VT2: 80.4 +/- 6.6 vs 87.0 +/- 5.9% (V) over dot O(2)max in EC and PC, respectively). La ctate levels showed a similar response in both groups at low-to-modera te intensities (< 300 W), and thereafter blood lactate was significant ly higher in EC. Finally, the ''electromyographic threshold'' (EMG,) o ccurred at a significantly higher intensity (p < 0.05) in PC when comp ared to EC (64.7 +/- 14.2 vs 56.0 +/- 14.9% (V) over dot O(2)max, resp ectively). It was concluded that, in comparison with EC, PC exhibit so me remarkable physiological characteristics such as a high VT,, an imp ortant reliance on fat metabolism even at high power outputs, and seve ral neuromuscular adaptations.