Too much of a good workout? Research says intense exercise may be unhealthy

Published 4:22 pm Monday, March 14, 2016

While many would consider athletes the healthiest people on the planet, there’s a growing body of evidence that very intense exercise can be bad for the heart.

In some people, high intensity cardio could cause structural changes, which can lead to arrhythmias, or irregular heartbeat.

However, this phenomenon is somewhat difficult to study, since the smallest suggestion that exercise might be bad for one’s health is enough to bring down a mass of criticism. A recent review published in the Canadian Journal of Cardiology looked at all the research that has been done on this subject, as well as the issues and controversies that arise when studying a possible negative relationship between heart health and exercise.

“Much of the discussion regarding the relative risks and benefits of long-term endurance sports training is hijacked by definitive media-grabbing statements, which has fueled an environment in which one may be criticized for even questioning the benefits of exercise,” explained Dr. André La Gerche, head of Sports Cardiology at the Baker IDI Heart and Diabetes Institute in Melbourne, Australia. “This paper discusses the often questionable, incomplete, and controversial science behind the emerging concern that high levels of intense exercise may be associated with some adverse health effects.”

A prevalent theory is that only people with inherited risk or a preexisting condition develop heart problems due to exercise. Dr. La Gerche argues that isn’t the case by excluding those with existing conditions from his review. He found that the negative correlation between heart health and intense cardiac exercise still existed, indicating that the exercise itself caused the heart problems.

However, he also found that there are a lot of holes in the data that need to be filled before proceeding, which means that the scientific community must put aside their biases in order to study the correlation.

“The answers regarding the healthfulness of ‘extreme’ exercise are not complete and there are valid questions being raised,” continued Dr. La Gerche. “Given that this is a concern that affects such a large proportion of society, it is something that deserves investment. The lack of large prospective studies of persons engaged in high-volume and high-intensity exercise represents the biggest deficiency in the literature to date, and, although such work presents a logistical and financial challenge, many questions will remain controversies until such data emerge.”