Acute physiological effects of interval versus steady-state exercise
File(s)
Date
2010-05-24Author
Horlitz, Sarah
Advisor(s)
Steffen, Jeffrey
Foster, Carl
Porcari, John
Metadata
Show full item recordAbstract
This study was designed to evaluate the exercise intensity and energy expenditure of interval exercise compared to steady-state exercise on a cycle ergometer. Fourteen subjects completed a VO2max test on a cycle ergometer to determine their aerobic capacity. Subjects then completed an interval ride and a steady-state ride. The interval ride alternated one minute of high-intensity cycling at 90% of maximal power output followed by one minute of active rest for 20 minutes. The steady-state ride consisted of 20 minutes exercise at 90% of the subject's ventilatory threshold (VT). Total work was matched between conditions. Oxygen consumption (V02), heart rate (HR), lactate, and RPE values were measured. After completion of both trials, a post-exercise questionnaire was administered. No significant difference (p<.05) was found in HR between the rides (142 + 14.9 vs. 145 + 13.7). There were significant differences between the interval ride vs. steady-state ride for VO2 (31.2 + 6.05 vs. 29.9 + 5.97), lactate (4.8 + 2.19 vs. 2.1 + 1.64), and RPE (5.6 + 1.3 vs. 3.8 + .83). Interval exercise elicits 9% higher energy expenditure than steady-state exercise and may be an effective way to obtain cardiovascular benefits for individuals with limited time.
Subject
Exercise -- Physiological aspects
Cycling -- Physiological aspects