Which class of medication has the greatest influence on resting and exercise heart rate?

Beta blockers are a class of medications that primarily influence the cardiovascular system by blocking the effects of adrenaline (epinephrine) on beta-adrenergic receptors. This action reduces heart rate and myocardial contractility, leading to a lower resting heart rate and a decreased heart rate response during exercise. As a result, individuals taking beta blockers typically experience a dampened heart rate response to physical activity, which can be an important consideration in exercise prescription and monitoring.

In contrast, angiotensin converting enzyme inhibitors (ACE inhibitors) primarily manage blood pressure and may not have a direct impact on heart rate. Statins are used to lower cholesterol levels and have various cardiovascular benefits, but their effect on heart rate is not significant. Diuretics help manage fluid balance and reduce blood pressure by promoting urine production, but they do not have a direct effect on heart rate regulation.

This makes beta blockers the most influential medication on resting and exercise heart rate among the options provided.