Journal of Applied Physiology, Vol 58, Issue 2 431-435, Copyright © 1985 by American Physiological Society
Central control of cardiovascular adjustments to exercise
A. Perski, S. P. Tzankoff and B. T. Engel
Voluntary heart rate (HR) control during moderate exercise on a bicycle
ergometer was studied in 10 healthy physically conditioned men (5
experimental and 5 control). The results showed that subjects could learn
to attenuate the tachycardia of exercise while exercising at a steady work
level of 60-70% of maximum HR. Experimental subjects who saw beat-to-beat
displays of HR and were instructed to slow HR showed 22% less increase in
HR than did control subjects who exercised without HR displays or
instruction to slow HR (42.6 vs. 54.6 beats/min). When the control subjects
were given feedback in additional sessions, they also decreased HR
significantly by 9% (54.6 vs. 49.9 beats/min). Analyses of concomitant
respiratory and metabolic data showed that HR attenuation was accompanied
by decreased O2 consumption (P less than 0.06) and pulmonary ventilation (P
less than 0.01). Rate pressure product also fell, indicating a decrease in
myocardial O2 consumption. Comparisons among pre- and postsubmaximal and
cardiovascular pulmonary and humoral responses during maximal test sessions
suggested that the improvement in cardiopulmonary function during feedback
training occurred with no sacrifice to working muscle requirements because
blood lactate concentrations were similar. The attenuation of the HR
response obtained in the present study indicates that feedback training in
physically conditioned subjects can influence cardiovascular responses even
under conditions of heavy local demands imposed by working muscles.
