Freely Chosen Cadence is Increased during Repeated Bouts of Submaximal Ergometer Pedalling

It was investigated whether the phenomenon of repeated bout rate enhancement occurs during submaximal ergometer cycling. Repeated bout rate enhancement is defined as an increase of the freely, or spontaneously, chosen cadence during repeated bouts of pedalling and has previously been reported for finger tapping. This is relevant to study since cadence can affect biomechanical and physiological responses. Recreationally active individuals (n=27) performed five consecutive 5-min bouts of cycling at 100 W using freely chosen cadence. All bouts were separated by 10-min rest. Cadence, pedal force profile characteristics, heart rate, tympanic temperature, and rate of perceived exertion were determined during cycling. The primary result was that cadence at the end of 5. bout was statistically significantly higher than at the end of all other bouts. Overall, the cadence at the end of 5. bout was 15.6%±20.4% higher than at the end of 1. bout. The altered rhythmic motor behaviour was accompanied by a statistically significant effect of bout on the pedal force profile. Also, there was a statistically significant effect of bout on heart rate, which amounted to 125±17 and 131±26 beats/min at the end of 1. and 5. bout, respectively. Perhaps the observed increase of cadence occurred as a nonconscious rhythmogenesis process in form of a net excitation of relevant parts of the nervous system. In conclusion, repeated bout rate enhancement during submaximal ergometer cycling occurred. The freely chosen cadence showed an increase of on average about 15%, or 10 rpm, as accumulated values across five bouts of cycling.