Physiological effects of variations in spontaneously chosen crank rate during incremental upper-body exercise.
The aims of the present study were: first, to assess the interindividual variations of a spontaneously chosen crank rate (SCCR) in relation to the power developed during an incremental upper body exercise on an arm ergometer set at a constant power regime, and second, to compare heart rate (HR) responses, expired minute ventilation (V[E]) and oxygen consumption (VO2) when the pedal rates were chosen spontaneously (T[SCCR]) or set at +/- 10% of the freely chosen rates (T[+10%] and T[-10%], respectively). The mean pedal rate values were linearly related (P < 0.01) with the power developed during arm cranking (r = 0.96), although large variations of pedalling rate strategies were observed between subjects. Maximal power (MP) and time to exhaustion values were significantly higher (P < 0.05) during T(SCCR) than during T(+10%) and T(-10%). Peak VO2 values were significantly higher (P < 0.05) in T(+10%) than in T(SCCR) and T(-10%). The increase in HR, V(E), and VO2 mean values, in relation to the increase in the power developed, was significantly higher (P < 0.05) when the pedal rate was set at plus 10% of the SCCR (T[+/-10%]) than in the two other conditions. The findings of the present study suggest that the use of an electromagnetically braked ergometer, which automatically adjusts the resistance component to maintain a constant work rate, should be used in order to achieve the highest MP values during an incremental upper body exercise. A 10% increase of the SCCR should be used in order to provide the highest peak VO2 value.
Weissland
T
T
Laboratoire d'Etudes de la Motricité Humaine, Faculté des Sciences du Sport et de l'Education Physique, Université de Lille II, Ronchin, France.
Pelayo
P
P
Vanvelcenaher
J
J
Marais
G
G
Lavoie
J M
JM
Robin
H
H
D000328:Adult; D001132:Arm / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D016552:Ergometry; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology