A COMARISON OF THE PHYSIOLOGICAL AND PERCEPTUAL RESPONSES TO UPRIGHT AND RECUMBENT CYCLING:

The purpose of this investigation was to compare the physiological and perceptual responses to upright (UP) and recumbent (RE) cycling. Twelve men and women (age, 23.5 ± 5.2 yr, VO2max, 36.9 ± 5.2 ml.kg-1.min-1, body fat, 17.0 ± 5.4%) completed four randomly assigned 30-minute cycling trials. Subjects performed an estimation trial (EST) and a production trial (PRO) on an upright and a recumbent cycle ergometer. During EST subjects maintained a workload of 65% of VO2max. During PRO subjects maintained a workload corresponding to an RPE of õ13-Somewhat hardö. Control consoles were covered to insure that subjects were unaware of power output or elapsed time. Pedal speed remained constant at 70 rpm. Oxygen consumption (VO2,), heart rate (HR) and minute ventilation (VE) were measured continuously throughout the trials. Lactate, peripheral RPE (P-RPE), respiratory-metabolic RPE (RM-RPE) and overall RPE (O-RPE) were measured at minutes 10, 20 and 30. During EST VO2 was similar between UP and RE (64.5 ± 1.4% VO2max and 65.4 ± 2.2%VO2max, respectively). HR response to UP (80.4 ± .07%HRmax) was higher (P < 0.05) than RE (77.2 ± .06%HRmax). During PRO, VO2 was higher (p < 0.05) during UP (70.4 ± 7.6%VO2max) compared to RE (65.6 ± 7.8%VO2max). UP had a greater (p < 0.01) heart rate response (83.8 ± .06%HRmax) compared to RE (78.7 ± 0.7%HRmax). There were no significant differences between UP and RE for lactate, VE, P-RPE, RM-RPE or O-RPE during EST or PRO. Energy expenditure was significantly greater (p < 0.01) during UP-PRO (289.6 ± 57.3 kcal) than UP-EST (267.4 ± 57.0 kcal) RE-PRO (266.6 ± 54.5 kcal) RE-EST (270.5 ± 57.4 kcal). These findings suggest that upright cycling elicits a higher heart rate response compared to recumbent cycling during equal intensity exercise. Additionally, at an O-RPE of 13 individuals self-select a higher intensity during upright compared to recumbent cycling. This results in increased caloric expenditure and may produce greater gains in cardiorespiratory fitness.