Respiratory exchange ratio in aerobic exercise on treadmill versus cycle ergometer at similar perceived exertion

Abstract

Background: Treadmill (TM) and cycle ergometer (CE) are the most commonly used indoor machines for aerobic exercise (AE). Previous studies have indicated that TM causes higher fat oxidation than CE AE; however, data from the Indian subcontinent are lacking regarding the same. Accumulation of visceral fat leads to various cardiovascular and metabolic disorders, and hence, AE modality that causes higher fat oxidation could prove more beneficial in improving health-related quality of life. Aims and Objectives: The aim of this study is to compare cardiovascular response and respiratory exchange ratio (RER) in TM and CE AE by moderately active males at similar ratings of perceived exertion (RPE). Materials and Methods: In the present experimental study, sixteen males with normal body mass index were involved to perform 30 min of continuous moderate intensity AE on TM and CE at RPE of 13. Systolic blood pressure (SBP) and diastolic blood pressure (DBP), heart rate (HR), and pulse pressure (PP) were analyzed just before and after the exercise trial. RER was estimated during the last 2 min of exercise. Paired t-test was applied to compare the means, and P < 0.05 was considered statistically significant. Results: HR after TM (136 ± 10) tended (P = 0.063) to be higher than CE (132 ± 9), while changes in SBP, DBP, and PP were non-significant. RER was non-significantly (P = 0.148) higher in CE (0.89 ± 0.05) than TM (0.91 ± 0.06). Oxygen consumption was significantly (P = 0.049) higher in TM (1.11 ± 0.17 L/min) than CE (1.03 ± 0.16 L/min). Conclusion: TM caused significantly higher energy consumption with non-significantly higher HR and fat oxidation than CE AE at RPE of 13.