Nenne die Quellen für die Empfehlung für den genannten Abzug der 10-20% bei

The American Heart Association (AHA) and the American College of Sports Medicine (ACSM) recommend a 10–20% reduction in training intensity when using beta-blockers to account for their impact on heart rate response during exercise. This adjustment is to accommodate the beta-blockers’ pharmacological effect of lowering maximal heart rate, which may underestimate exercise intensity if based solely on heart rate metrics. The ACSM guidelines emphasize individualized exercise prescription considering medications that affect heart rate, such as beta-blockers, advising clinicians to reduce target training intensity by approximately 10–20% when relying on heart rate zones for exercise intensity guidance Komici et al. 2026.

This recommendation is grounded in the practical exercise prescription framework that incorporates the FITT principles (Frequency, Intensity, Time, and Type) and acknowledges that beta-blockers blunt the expected increase in heart rate during exercise. Therefore, target heart rates used to prescribe exercise intensity or to monitor training load must be correspondingly lowered to ensure safety and effectiveness Komici et al. 2026.

Further, the guidelines note that exercise intensity can be estimated through multiple methods, including heart rate reserve, percentage of maximal heart rate, oxygen uptake (VO2), metabolic equivalents (METs), or perceived exertion scales (RPE). When beta-blockers are used, reliance on non–heart rate-based measures or subjective exertion scales may provide more accurate guidance. When heart rate measures are used, the reduced maximal heart rate effect of beta-blockade necessitates a 10–20% decrease in target training intensity to prevent overexertion Komici et al. 2026.

Although the recent scientific literature included does not specifically address the exact figure of 10–20% reduction in training intensity with beta-blocker use, it supports the need for individualized and carefully monitored exercise prescriptions in patients with cardiovascular conditions and those on medications affecting heart rate. It emphasizes that exercise programs should be tailored considering medication effects, comorbidities, and safety, aligning with the ACSM recommendations Djuranovic et al. 2025,Pham et al. 2025,Komici et al. 2026.