July 7, 2007

The effect of antecedent fatiguing activity on the relationship between perceived exertion and physiological activity during a constant load exercise task

Q: What is the clinical evidence from this study?

Study design: Other. Intervention: Antecedent fatiguing activity vs. Fresh state condition. Primary outcome: Relationship between the rate of change of the rating of perceived exertion (RPE), physiological activity, and time to volitional exhaustion.

Key Result

Antecedent fatiguing activity increased the rate of increase in RPE compared to a fresh state, but there were no differences when expressed against percentage of time to exhaustion.

Structured PICO

Does antecedent fatiguing activity alter the relationship between perceived exertion and physiological activity during constant load exercise?

Population

10 participants who completed constant load exercise tests to exhaustion in fatigued and fresh states.

Intervention

Constant load cycling at 75% peak oxygen uptake (VO2peak) to exhaustion in a fatigued condition (after a graded exercise test)

Comparator

Constant load cycling at 75% VO2peak to exhaustion in a fresh state condition

Outcome

Relationship between the rate of change of the rating of perceived exertion (RPE), physiological activity, and time to volitional exhaustionpatient reported

RPE appears to be set at the start of exercise using a scalar internal timing mechanism that adjusts to physiological parameters altered by previous fatigue.

Abstract

This study assessed the relationship between the rate of change of the rating of perceived exertion (RPE), physiological activity, and time to volitional exhaustion. After completing a graded exercise test, 10 participants cycled at a constant load equating to 75% of peak oxygen uptake (V O(2)peak) to exhaustion. Participants performed two further constant load exercise tests at 75%V O(2)peak in a fresh state condition within the next 7 days. The RPE was regressed against time and percentage of the time (%time) to volitional exhaustion in both conditions. Despite a lower respiratory exchange ratio (RER) and higher heart rate at the start of the exercise bout in the fatigued condition, there were no differences in RPE at the onset or completion of exercise. As expected, the rate of increase in RPE was greater in the fatigued condition, but there were no differences when expressed against %time. Results suggest that RPE is set at the start of exercise using a scalar internal timing mechanism, which regulates RPE by altering the gain of the relationship with physiological parameters such as heart rate and RER when these are altered by previous fatiguing exercise.

Demander à l'IA

Bookmark