Extreme exercise found not to increase risk of cardiovascular disease, say scientists

Extreme exercise doesn’t increase cardiovascular disease risk

In 2017 a scientific study found that middle-aged athletes are more at risk of calcium building up in the arteries, however that doesn’t make them more prone to the heart becoming compromised and injured, a new study has found.

“The question has never been whether exercise is good for you, but whether extreme exercise is bad for you. For the past decade or so, there’s been increasing concern that high-volume, high-intensity exercise could injure the heart. We found that high volumes of exercise are safe, even when coronary calcium levels are high,” lead author sports cardiologist Dr. Benjamin Levine, who is Professor of Internal Medicine and Director of the Institute for Exercise and Environmental Medicine, collaboration between UT Southwestern Medical Center and Texas Health Presbyterian Hospital Dallas.

Using data from the Cooper Center Longitudinal Study Dr. Levine studied the stats on 21,758 generally healthy men, aged 40 to 80, without cardiovascular disease, who were followed for mortality between 1998 and 2013. The athletes, the majority of them in middle age, reported their physical activity levels and underwent regular coronary calcium scanning. Most were predominantly runners, but some were cyclists, swimmers, or rowers. There was also a subgroup of triathletes.

Coronary calcium scanning is an imaging test that helps medics classify patients without cardiac symptoms as low, intermediate, or high risk for heart attack. It represents how much calcium (and thus cholesterol deposits) has accumulated in the blood vessels that supply the heart. The scan can help physicians determine the need for medication, lifestyle modification, and other risk-reducing measures.

The majority of the high-intensity athletes in the study had low levels of coronary calcium, though their odds of having higher levels were 11% greater than men who exercised less. Most importantly, the researchers found that higher calcium scores did not raise the high-intensity athletes’ risk for cardiovascular or all-cause mortality.

“Calcium is simply to footprint of atherosclerosis; that is, a marker of the presence of the atherosclerotic process,” said Dr. Levine. It is not actually the calcified plaque that we are worried about though, and calcified plaques are more stable, and less likely to rupture and cause a heart attack.

“The current study shows no increased risk of mortality in high-volume exercisers who have coronary artery calcium. Certainly, these high-volume exercisers should review their cardiovascular disease risk with their primary care doctor or cardiologists and the study results provide helpful clinical guidance.”

“The most important take-home message for the exercising public is that high volumes of exercise are safe. The benefits of exercise far outweigh the minor risk of having a little more coronary calcium.”

The study is now published in JAMA Cardiology

About

Dr Benjamin Levine is the founder and director of the Institute for Exercise and Environmental Medicine (IEEM) at Texas Health Presbyterian Hospital Dallas. He is also professor of internal medicine/cardiology and distinguished professor of exercise sciences at the University of Texas Southwestern Medical Center. Dr Levine earned his B.A. magna cum laude in human biology from Brown University and his M.D. from Harvard Medical School. He completed his internship and residency in internal medicine at Stanford University Medical Center followed by a cardiology fellowship at UT Southwestern where he trained under the renowned cardiovascular physiologists Gunnar Blomqivst, M.D. and Jere Mitchell, M.D. Dr Levine founded the IEEM in 1992, which has become one of the premier laboratories in the world for the study of human clinical and integrative physiology. His global research interests centre on the adaptive capacity of the circulation in response to exercise training, deconditioning, aging, and environmental stimuli such as spaceflight and high altitude. A Henry Luce Foundation and Fulbright Scholar, he received the Peter van Handel Award from the United States Olympic Committee (for outstanding research), the Research Award from the Wilderness Medical Society, the Honor Award from the Texas Chapter of American College of Sports Medicine (ACSM), and the Citation Award from the National ACSM for his body of work. A consummate clinician and teacher as well as a scholar, he was elected to the Association of University Cardiologists, the American Association of Physicians, received the Michael J. Joyner International Teaching Award from the Danish Cardiovascular Research Academy, and has been selected as one of the ‘Best Doctors’ for cardiovascular medicine in Dallas and America multiple times by his peers. Dr Levine is a renowned sports cardiologist who sees athletes with cardiovascular medical problems from around the world and serves as a consultant to the NCAA, the NHL, the NFL, the USOC, USA Track and Field, and other athletic organisations. He’s been a key contributor to the guidelines for the management of athletes with heart disease since 1994. Dr Levine also has a unique background in space medicine, serving as a co-investigator on 4 Spacelab missions (SLS-1, SLS-2, D-2 and Neurolab), the MIR space station, and recently was the PI of a large cardiovascular experiment on the International Space Station (ISS), called the ‘ICV’. He was also awarded by NASA the “most Compelling Results from the ISS” in 2013. He currently advises NASA’s flight surgeons on cardiovascular medical issues. Dr Levine has published over 300 peer-reviewed journal articles, reviews, book chapters, and technical papers, and is currently serving on the editorial boards of numerous journals. Dr Levine is a Fellow of the American College of Sports Medicine (ACSM), American Heart Association, the American College of Cardiology, and the Cardiovascular Section of the American Physiological Society.