While I’m the first to agree that the prescription for health for most of us is to eat better and exercise more, there’s another important message that seldom gets airtime. That being: when it comes to exercise, more isn’t necessarily better. It’s true that the average person today probably doesn’t get the exercise they need. However, being active and fit doesn’t mean you have to work out at the gym for two hours each day or run a marathon.
In fact, doing either of those things could very well harm your heart rather than helping it.
It’s true that most of us are far more likely to under-exercise than to over-exercise. But for the truly fitness-minded a word of caution is in order. While working out up to an hour per day has huge health benefits, going beyond that hour doesn’t have much of an additional effect. And if you have a grueling cardio training schedule, you could actually end up with scar tissue in your heart.
This research gives a whole new meaning to the term “hard-hearted”
Most of the research so far has been done with hard-core athletes. In particular, marathon runners and other endurance athletes. We’ve long known that serious athletes often develop abnormal EKG readings. And endurance athletes especially — like marathon runners or professional cyclists — are prone to developing a dangerous heart condition called atrial fibrillation.
In atrial fibrillation, the upper two chambers of the heart beat out of sync with the rest of the heart. This usually goes hand-in-hand with other health issues like coronary artery disease, high blood pressure, or heart attacks. Any type of heart diseases is a risk factor. So are obesity and diabetes. It’s no surprise when the sedentary or the sickly end up with atrial fibrillation.
Endurance athletes, though, should be the healthiest of the healthy. Heart problems should be the farthest thing from their minds. However, this group is a whopping five times more likely than the general public to develop atrial fibrillation. This shocking statistic led researchers to take a serious look at just what effect extreme exercise has on your heart.
What they found was surprising to say the least. Intense training causes stretching of the heart’s chambers. In the areas that experience this stretching, the heart’s ability to pump is reduced. Biomarkers that correspond to heart damage appear in the blood. Within a week or so, these things return to normal. So if you do one insanely tough workout, you’re probably not doing any lasting damage.
If, however, intense training is a part of your regular schedule, it can lead to scarring in your heart. In time, this causes the walls of your heart to stiffen. Your heart may be enlarged. And of course you run the risk of atrial fibrillation. Researchers from Ochsner Health System found that marathoners were three times as likely as others to have scarring in their hearts, and twice as likely to have a heart attack.
Should we treat exercise like a drug?
We all know that when it comes to medication, more isn’t necessarily better. Any medication powerful enough to have an effect usually has an upper limit, and taking more than directed can result in an overdose. It’s beginning to look as if this may be the case for exercise too.
Does this mean you should cut back on your hours at the gym or cycling the neighborhood? Probably not, unless you’re training for a triathalon. The research is clear that regular exercise is still one of the best things you can do for your heart. However, the same research has shown that for heart health, a moderate-intensity workout is just as beneficial as an intense one. And going above and beyond an hour per day just doesn’t seem to have any added benefit.
Instead, aim for half an hour to 45 minutes of moderate exercise. The best exercise for your heart is still the simplest. Brisk walking, bicycling, and swimming are all good choices. You can even turn your daily routine into a high intensity interval training (HIIT) workout that alternates one to two minutes of intense exercise with a shorter, lighter rest period. If you do choose to do a HIIT workout, keep the length to 20 minutes or so per day.
And if you’re a runner, you don’t need to give it up. Just don’t overdo it. The experts recommend running no more than 20 miles per week and spreading the miles out over several days. They also recommend keeping your speed to under five miles per hour. Once you get out of this range, you just might be doing more harm than good.