Abatement of exertional perceptions following dynamic exercise: physiological mediators.
Perceptual and physiological congruity was examined during recovery from high-intensity dynamic exercise. Nine males (24.8 +/- 0.6 yr; VO2max; 52.3 +/- 1.5 ml.kg-1.min-1) undertook in random order four maximal treadmill protocols. Treadmill speed was held constant (5.3 km.h-1) while grade was incremented by 2, 4, 6, or 8% every 3 min for protocols A, B, C, and D, respectively. Ratings of perceived exertion (RPErec; Borg 15-point scale), ventilation (VE), respiratory rate (RR), oxygen uptake (VO2), and heart rate (HR) were measured preexercise and during each min of a 12-min supine postexercise period that immediately followed treadmill testing. Ratings were obtained for the peripheral perceptual signal arising from the legs (RPErec-L), the respiratory-metabolic signal from the chest (RPErec-C), and the overall body signal (RPErec-O). Blood pH was measured preexercise and during min 1, 6, and 12 of recovery. RPErec-L and RPErec-O were lower (P less than 0.05) and blood pH higher (p less than 0.05) following protocol A than D at all recovery time points. RPErec-C, VE, and RR were lower (P less than 0.05) for protocol A than D at all recovery time points. Differences among protocols were not noted for VO2 or HR at any recovery time point. The decay in signal strength for both RPErec-L and RPErec-O following high-intensity exercise reflected the abatement of metabolic acidosis. RPErec-O was influenced by the abatement of pulmonary ventilation during the postexercise period.
Robertson
R J
RJ
Department of Health and Physical Education, School of Education, University of Pittsburgh, PA 15261.
Nixon
P A
PA
Caspersen
C J
CJ
Metz
K F
KF
Abbott
R A
RA
Goss
F L
FL
D000138:Acidosis / Q000503:physiopathology; D000328:Adult; D005221:Fatigue / Q000523:psychology; D006339:Heart Rate; D006801:Humans; D007866:Leg; D008297:Male; D010146:Pain / Q000523:psychology; D010465:Perception; D005082:Physical Exertion / Q000502:physiology*; D012129:Respiratory Function Tests; D013312:Stress, Physiological / Q000523:psychology; D013909:Thorax