Previous investigations have shown that metabolic rate remains elevated for a period of time after the cessation of exercise. While other investigations have examined the effect of intensity and duration of prior exercise, the purpose of this study was to examine the effect of exercise mode and the employment of different muscle masses on the elevation of post-exercise metabolic rate (EPOC). Fifteen non-smoking, physically active females (21.1 ± 1.3 years; 21.4 ± 4.6 %BF) volunteered for this investigation. Each subject completed a graded maximal exercise test (GXT) on the Monark 880 cycle ergometer (Max HR=192.5 ± 2.3 bpm; Max V02=2.68 ± O.lll/min; Max RPE=19.5 ± 0.1) from which a heart rate corresponding to 70% V02max was chosen. Subjects then exercised on either a Monark 880 cycle ergometer (LE) or the Schwinn Airdyne (ALE) in random order for thirty minutes at the prescribed heart rate (HR). Exercise bouts were separated from each other and from the GXT by at least 48 hours. Workloads were monitored in five minute intervals and adjusted to maintain the appropriate heart rate. The mean exercise heart rates were 172.5 ± 2.8 bpm for the LE bout and 170.0 ± 2.8 bpm for the ALE bout, respectively. Two-way repeated measures ANOVA revealed no significant difference \r >0.05) between exercise treatments in terms of HR or V02. Repeated measures trend analYSis revealed no significant difference in either EPOC or post-exercise heart rate between the two treatments across a one-hour seated recovery period. There was also no significant difference (p>O.05) in excess post-exercise caloric expenditure during the recovery period as a result of the different exercise treatments. Therefore, this suggests that neither exercise modality nor the distribution of work over a larger muscle mass had an effect on EPOC when exercise intensity and duration were held constant. / Master of Science