Postexercise energy expenditure following upper body exercise

Area of Science:

• Exercise Physiology
• Metabolic Responses to Exercise

Background:

• Excess postexercise oxygen consumption (EPOC) quantifies the oxygen uptake above resting levels after exercise.
• Understanding EPOC's determinants is crucial for exercise prescription and metabolic research.
• Previous studies have explored EPOC with lower body exercise, but upper body comparisons are less common.

Purpose of the Study:

• To compare the magnitude and duration of EPOC following upper body (arm crank) versus lower body (cycle ergometer) exercise.
• To investigate the relationship between EPOC and exercise intensity (VO2) and active muscle mass.
• To determine if relative metabolic rate influences EPOC independently of exercise modality.

Main Methods:

• Eight healthy subjects (4 male, 4 female) participated in a counterbalanced crossover study.
• Subjects performed 20-minute exercise sessions at 60% of mode-specific peak oxygen uptake (VO2) on an arm crank and cycle ergometer on separate days.
• Baseline and postexercise oxygen consumption (VO2) and heart rate (HR) were continuously monitored until baseline VO2 was reestablished.

Main Results:

• No significant differences were observed in the magnitude of EPOC between arm crank (9.2 +/- 3.3 kcal) and cycle ergometer (10.4 +/- 5.8 kcal) exercise.
• The duration of EPOC was also not significantly different, with values of 22.9 +/- 13.7 min for upper body and 24.2 +/- 19.4 min for lower body exercise.
• These results indicate similar EPOC responses despite differences in the muscle mass utilized.

Conclusions:

• EPOC magnitude and duration are comparable between upper and lower body exercises under the studied conditions.
• The findings suggest that the relative metabolic rate of the active musculature, rather than absolute exercise VO2 or the quantity of active muscle mass, is a primary determinant of EPOC.
• This implies that exercise modality may be less critical for EPOC than the intensity relative to the engaged muscle group's capacity.