Abstract
We determined if high cadences, during a prolonged cycling
protocol with varying intensities (similar to race situations)
decrease performance compared to cycling at a lower, more
energetically optimal, cadence. Eight healthy, competitive male
road cyclists (35 ± 2 yr) cycled for 180 min at either 80 or 100
rpm (randomized) with varying intensities of power outputs
corresponding to 50, 65 and 80% of VO2max. At the end of this
cycling period, participants completed a ramped exercise test to
exhaustion at their preferred cadence (90 ± 7 rpm). There were
no cadence differences in blood glucose, respiratory exchange
ratio or rate of perceived exertion. Heart Rate, VO2 and blood
lactate were higher at 100 rpm vs. 80 rpm. The total energy cost
while cycling during the 65% and 80% VO2max intervals at 100
rpm (15.2 ± 2.7 and 19.1 ± 2.5 kcal·min-1, respectively) were
higher than at 80 rpm (14.3 ± 2.7 and 18.3± 2.2 kcal·min-1,
respectively) (p < 0.05). Gross efficiency was higher at 80 rpm
vs. 100 rpm during both the 65% (22.8 ± 1.0 vs. 21.3 ± 4.5%)
and the 80% (23.1 vs. 22.1 ± 0.9%) exercise intensities (P<
0.05). Maximal power during the performance test (362 ± 38
watts) was greater at 80 rpm than 100 rpm (327 ± 27 watts) (p <
0.05). Findings suggest that in conditions simulating those seen
during prolonged competitive cycling, higher cadences (i.e., 100
vs. 80 rpm) are less efficient, resulting in greater energy expenditure
and reduced peak power output during maximal performance.