Journal of Applied Physiology, Vol 51, Issue 2 516-519, Copyright © 1981 by American Physiological Society
Comparison of heart rate measurement protocols used during autonomic function tests
W. B. Baun, A. Jackson, R. W. Patton and P. B. Raven
The five most used cold pressor test heart rate protocols were compared to
the true R-R interval responses recorded during a cold hand test. Forty-one
nonsmoking male volunteers between 18 and 55 yr were given a cold hand
pressor test. Heart rate was evaluated by averaging the R-R interval within
2-, 5-, 6-, 10-, and 30-s time intervals and by the true R-R interval
measurement. No significant physiological differences existed at rest;
however, during stress the maximum values obtained were successively
diminished the greater the time utilized to average the heart rate pressure
(P less than 0.05). During recovery an underestimation of the true response
was observed that increased as the averaging time increased (P less than
0.05). Comparison between the R-R interval measure and the 6-s average data
indicated a 18% decrease in the time of peak response. Therefore, the
responses recorded with the 6-s averaged data were less sensitive and
obscured the rapidity of autonomic changes. Hence, when sensitivity and
absolute response are a primary concern in determining autonomic function,
measurements should include R-R interval measures of heart rate or the
average of the number of R-R intervals in 2-s time blocks.
