Influence of propranolol on exercise prescription of training heart rates.

Review of a longitudinal study of the effects of 40 mg of propranolol orally in 14 patients with coronary heart disease demonstrated a minor but not statistically significant change in the relationship of percentage of maximal oxygen uptake to percentage of maximal heart rate. In a cross-sectional comparison of several hundred patients who showed no other significant difference in initial findings in relation to propranolol, significant differences were present with respect to resting heart rate and responses to symptom-limited exercise, nevertheless the relationship of percentage of maximal oxygen uptake to the percentage of maximal heart rate was similar. Accordingly, we recommend maximal exercise testing in all patients prior to undertaking an exercise program so that their maximal heart rate can be determined accurately and rational training heart rates advised. The exercise test should be performed with the patients taking medications they anticipate continuing during the period of physical training, and if a change in medications is subsequently made then the exercise test should be repeated.