Use of heart rate for evaluating cardiac strain during training in women

¹ Haskell Laboratory for Toxicology and Industrial Medicine, E. I. du Pont de Nemours and Co., Wilmington, Delaware

The usefulness of heart rate information to measure cardiac performance is demonstrated for young women during physical training. Data were studied in terms of rate, total number of beats (cardiac cost), and recovery phenomena. Provided work remained constant, training decreased the heart rate during both work and recovery, with corresponding reduction in the sum of beats (total cardiac cost). If working rates are not obtainable, recovery rates as 1) the sum of beats (recovery cost) or 2) P_{avg 1, 2, 3}, the average of counts taken during the last 30 sec of the 1st, 2nd, and 3rd min of the recovery period, can substitute for total cost as a measure of cardiac performance. The effect of increasing the work accomplished upon cardiac cost and P_{avg 1, 2, 3} is discussed and use of a comparative "standard" for assessing cardiac strain from the value of P_{avg 1, 2, 3} is suggested.

Submitted on March 17, 1964