Originally Posted by
merlinextraligh
I don't think anyone's debating that exercise is good for your heart. And 100 miles a week of recreational riding with some intervals thrown in isn't the "excessive exercise" that's at issue.
I think there is a real question of whether 200 miles a week, 6 days a week, doing intervals at 100% effort, and multiple days of racing still makes health sense in your 50's particularly if it's on top of a lifetime of doing that.
I think it's very likely that 100 miles or so a week of moderate recreational club rides, balanced with some other recreational activities thrown in gives you all the health benefit you can get, and that pushing to the very limit of what your capable of, which many Masters racers, and triathletes do, adds no health benefit, and likely increases your risk of sudden cardiac death, and problems like a fib.
So I think if you continue to race into your 50's, you should be honest with yourself, and realize the rationale for doing so is not better health.
And as one off anecdote, I have a 59 year old friend, lifetime bike racer, maybe 5% body fat, who just underwent ablation for A Fib.
Sample of one, but consistent with Zinn's and others experience.
I usually do 4 days a week moderate effort, which I'm not worried about, but I have started doing 2 days a week of absolute 100% effort intervals. 3 mins on, 3 mins off, repeat 6x or 1.5 mins on, 3 mins off, repeat 8x, or 10 mins on, 5 mins off, repeat 3x... that kind of thing, but my other riding is lower intensity and I'm getting a ton of sleep/recovery time.
In 8 weeks my blood pressure has gone from 120/75 to 106/52 (the lower number is where I was in my early 20's) and my resting heart rate has gone from 60 to 48 (several tests before and after). That's the part that worries me, as the article said that decreased resting heart rate could be a sign of enlarged heart. I went in and got an EKG and they said I was perfect, but I don't know that an EKG checks for everything. I'm 29 years old, 30 in a couple weeks.