Pulse count as a measure of energy expenditure

¹ Defence Institute of Physiology and Allied Sciences, Metcalfe House, Delhi, India

Studies were made on seven subjects who were given different grades of exercise on a bicycle ergometer with a workload varying from 50 to 600 kg-m/min. Calorie expenditure during performance of various tasks was calculated by collecting the expired gases during the steady state. Pulse rate was also recorded during this period. To estimate the error in using pulse rate for measuring energy expenditure, the same subjects were given various field tasks such as marching, running, hopping, hammering, etc. During performance of these tasks energy expenditure and pulse rate were also measured, using the same techniques. Linear correlation was obtained between the pulse rate and the energy expenditure in all the subjects. There are two components of each curve, one for the pulse rates below 95 and the other for pulse rates above 95. A significant difference also was found in the coefficient of variation for different subjects, showing that separate regression lines are required for each of them. The percentage of error between observed and predicted values of energy expenditure for both the ranges of pulse counts varied from 0.3 to 4.7 and from 0.6 to 7.0, respectively.