According to a research led by the US physicians, extreme exercises such as marathons, have the potential to damage the heart and do long term harm along with triggering rhythm abnormalities. In extreme cases, it may cause large arteries and can make structural changes to the heart, leading to long-term injuries.

Lead author Dr. James O’Keefe from Kansas City of the Saint Luke’s Hospital has said that even though health is benefitted by exercise, it could have an adverse effect if taken to extreme lengths.

In his words, physical exercise though may not be a drug but has the traits of a powerful pharmacologic agent since a daily routine of physical activity has the ability to treat as well as prevent many of the life killing diseases.

As said before, like any other pharmacologic agent, there exists a safe limit of upper dose and if that limit is crossed, the damages will greatly outnumber the benefits resulting in musculoskeletal trauma and cardiovascular stress.

BARN5E woman running outdoor

Dr. O’Keefe and his colleagues had in their research said though transient structural and cardiovascular changes occur due to extreme endurance training, all of them return to normal within a week. But yes, for some individuals, this process can be a non-existent one since it can lead to the development of patchy scarring of some of the areas of the heart over months and years of repetitive injury.

One study has found out that approximately 12 percent of healthy marathon runners showed a clear sign of having patchy scarring of the heart areas as compared to those runners who don’t do marathons. Furthermore, the review also said that it has been discovered that it is the athletes of elite level who develop abnormal electrocardiogram readings.

However, today, studies show that the changes in the heart can also be triggered by extreme exercise leading to rhythm abnormalities. And one of the main culprits is ultramarathon running or professional cycling which promotes atrial fibrillation or abnormal heart rhythms. Other heart problems can also be associated with chronic excessive sustained exercise such as artery stiffening.

Dr. O’Keefe had said though vigorous exercisers have low death and disability rates as compared to nonexercisers, it is vital to detect long duration exercisers who might put themselves at risk due to their rigorous routine.

He had also stressed that though many studies point out that physical exercise is good for people, yet it is not the case for most people since physically active people are much healthier than their counterparts.

But that doesn’t mean that exercise needs to be done excessively. This will lead to a point of diminishing returns since extreme exercise is not recommended for the benefit of cardiovascular health.


Moreover, aerobic exercise can be achieved through sports such as jogging, running, cycling, etc, but it’s a level that should be enough to raise the heart rate to 120 beats a minute or higher and should include a brisk walk and swimming. But then again, gardening or even taking a stroll is regarded as a healthy activity. People still need to understand the main difference between proper exercise and being physically active:

Physically active means walking swimming, gardening, playing outside with your kids, playing a sport etc, which is essential for well being, but PROPER EXERCISE should be brief, safe and intense enough, if you exercise too much and use the wrong method for exercise like jogging or running or cycling you are doing more harm than good.  Proper Exercise is like a medicine. Proper dosage is a requirement to reap maximum benefits from it.


Marcelo is the co-founder and Director of Exercise Physiology at Intense Health, Perth's #1 Private Strength Training and Nutrition Clinics.


Marcelo is the co-founder and Director of Exercise Physiology at Intense Health, Perth's #1 Private Strength Training and Nutrition Clinics.