Excess exercise hurts the heart
This shouldn't be a shocking finding. There are very few studies that will find that "Excess _____" is good for you.
Exercise is quite good for the heart, up to a point.The excess described here is serious excess... triathlon type stuff.
I am posting this partly to note a peculiarity of the heart. It's one of our biggest muscles and definitely the hardest working. And it is beneficial to make the heart stronger with aerobic exercise. But if you manage to exercise the heart in the way a bodybuilder exercises a bicep you'll be in trouble. Unlike a bicep, you don't want your heart to get bigger. (And the oxygen deprivation that in a bicep is a "good burn" would, in the heart muscle, be considered a mild heart attack.)
Excess exercise 'hurts the heart' and cause dangerous long-term harm, say scientists
By Jenny Hope
Extreme exercise such as marathons may permanently damage the heart and trigger rhythm abnormalities, warn researchers.
They say the safe upper limit for heart health is a maximum of an hour a day - after which there is little benefit to the individual.
A review of research evidence by US physicians says intensive training schedules and extreme endurance competitions can cause long-term harm to peoples hearts.
Activities such as marathons, iron man distance triathlons, and very long distance bicycle races may cause structural changes to the heart and large arteries, leading to lasting injury.
Lead author Dr James OKeefe, of Saint Lukes Hospital of Kansas City, said exercise was generally beneficial for health but could tip into becoming harmful when taken to excessive lengths.
Activities such as marathons, iron man distance triathlons, and very long distance bicycle races may cause structural changes to the heart and large arteries, leading to lasting injury.
Read more:
http://www.dailymail.co.uk/health/article-2154267/Excess-exercise-hurts-heart-cause-dangerous-long-term-harm-say-scientists.html#ixzz1www0rnHZ