The effects of muscle mass on metabolic responses and perceived exertion during prolonged exercise

Author

Michael Faine Shipe

Date of Award

5-1997

Degree Type

Thesis

Degree Name

Master of Science

Major

Human Performance and Sport Studies

Major Professor

David R. Bassett

Committee Members

Edward T. Howley, Dixie L. Thompson

Abstract

This study compared the effects of arm and leg (A+L) and leg (L) exercise on metabolic responses and ratings of perceived exertion, using an air-braked cycle ergometer (Schwinn Air-Dyne). Twelve healthy subjects performed a maximal graded exercise tests with L and A+L. Subsequently, they performed a 30 minute exercise bout at 70% of VO_2max using L and A+L. Oxygen uptake (VO₂), ventilation (V_E), respiratory exchange ratio (R), heart rate (HR) and ratings of perceived exertion (RPE) were measured throughout all tests. Venous blood samples were taken 3-5 minutes after incremental test completion and at 10 minute intervals during the endurance test. Using planned contrasts, it was determined that RPE and R values for A+L exercise were significantly lower (p < 0.05) compared to L exercise at 147, 171, 196, and 221 Watts during the incremental test. In addition, VO₂ was higher for A+L versus L exercise at 74, 122, 147, 171, and 196 Watts (p<0.05). RPE, blood LA, and R values were significantly higher (p < 0.05) for L compared to A+L exercise throughout the endurance test. These results demonstrate that during prolonged work at moderately high intensities, RPE, R, and blood LA are lower for combined A+L versus L work. Further, the decrease in RPE appears to be due to a reduction in peripheral factors (blood LA and muscle strain) during A+L exercise.

Key words: ratings of perceived exertion, oxygen uptake, VO_2max, blood lactate accumulation, respiratory exchange ratio, heart rate, and power output.

Recommended Citation

Shipe, Michael Faine, "The effects of muscle mass on metabolic responses and perceived exertion during prolonged exercise. " Master's Thesis, University of Tennessee, 1997.
https://trace.tennessee.edu/utk_gradthes/10711