To determine the acute effects of rebound exercise in sedentary women (X̄ age = 28.0 ± 1.0 years), 17 subjects jogged and bounced according to two separate 18-minute graded exercise testing protocols. These protocols included 6, 3-minute stages with gradually increasing rates of jogging steps or bounces per minute, with rate controlled by a metronome. Mean values for VO2 and heart rate decreased from 1.52 l · min-1 and 166 beats per minute to 1.19 l · min-1 and 158 beats per minute when progressing from 90 to 140 bounces · min-1, while mean values for jogging increased from 1.36 l · min-1 and 157 beats per minute to 1.55 l · min-1 and 183 beats per minute when progressing from 105 to 205 steps · min-1. In contrast to the mode of jogging, there was an inverse relationship between energy expenditure and ratings of perceived exertion during incremental bouncing. V̇O(2max) values attained with the bouncing protocol produced only 76% of the value attained on a continuous incremental graded treadmill exercise test, while the V̇O(2max) attained with jogging reached 80% of the graded exercise test value. These data suggest that substantially different physiological responses are elicited from rebounding depending on whether bouncing or jogging is selected as the mode of exercise.