Top Things to Know: Exercise-Related Acute CV Events and Potential Deleterious Adaptations Following Long-Term Exercise Training
Published: February 26, 2020
Prepared by Barry A. Franklin, PhD, FAHA
- The benefits of regular moderate-to-vigorous physical activity (PA) and the associated improvements in cardiorespiratory fitness (CRF) far outweigh the risks for most individuals.
- Ostensibly healthy, inactive individuals starting to exercise should begin slowly, generally with a walking program, increasing the volume and intensity of exercise as their tolerance permits, provided they remain asymptomatic.
- As exertion-related acute cardiovascular (CV) events are often preceded by warning symptoms, patients should be strongly advised that symptoms require immediate cessation of endurance training/competition and medical review.
- The observation that vigorous PA and high levels of CRF are associated with reduced use of diabetic, blood pressure and cholesterol medications suggest that high-volume and high-intensity endurance training regimens are cardioprotective in individuals with and without coronary heart disease (CHD).
- The favorable risk factor profiles and superb cardiac performance of long-distance runners, as well as the anti-aging effects of exercise, have likely contributed to the escalating numbers of adults who have embraced the notion that “more exercise is better.”
- Unaccustomed vigorous physical activity, particularly when performed by inactive, unfit, susceptible individuals, can acutely increase the risk of sudden cardiac death (SCD) and acute myocardial infarction. Therefore, for those who are highly sedentary, it is important to start being physically active in an incremental way.
- Extreme endurance exercise training regimens are associated with potential cardiac maladaptations in some individuals, including accelerated coronary artery calcification (CAC), elevated cardiac biomarker release, myocardial fibrosis, and atrial fibrillation, which may be described by a reverse J-shaped dose-response curve.
- A higher prevalence of elevated CAC has been reported among endurance athletes versus matched controls; however, the risk for adverse CV events is lower in fit/active persons compared to their unfit/inactive counterparts with the same CAC score.
- Preliminary studies suggest potential adverse effects of endurance exercise in patients with arrhythmogenic right ventricular cardiomyopathy, long QT syndrome and inherited disorders of cardiac structural proteins such as lamin A/C mutations.
- Although high-intensity interval training (HIIT) is a purported time-saving alternative to moderate-intensity continuous training, providing slightly greater increases in cardiorespiratory fitness (CRF), concerns regarding the safety of repeated near-maximum exercise bouts in patients with known or suspected CV disease should be the foremost consideration prior to beginning HIIT, especially in nonmedical settings.
Citation
Franklin BA, Thompson PD, Al-Zaiti SS, Albert CM, Hivert M-F, Levine BD, Lobelo F, Madan K, Sharrief AZ, Eijsvogels TMH; on behalf of the American Heart Association Physical Activity Committee of the Council on Lifestyle and Cardiometabolic Health; Council on Cardiovascular and Stroke Nursing; Council on Clinical Cardiology; and Stroke Council. Exercise-related acute cardiovascular events and potential deleterious adaptations following long-term exercise training: placing the risks into perspective–an update: a scientific statement from the American Heart Association [published online ahead of print February 26, 2020]. Circulation. doi: 10.1161/CIR.0000000000000749.