Sorry, I think this is a more appropriate place because the question is about the value of cardio, its risks and benefits, etc. for older people. I haven't finished my digging yet, but I've had a few people tell me that its bad for older people. I didn't want the thread muddied with a bunch of 30 year old enduro junkies swearing that its the best because they eat, sleep, and breathe triathlons.
So what say you?
I believe the jury is still out on this. Most of the concern over exercise,and heart issues, started a few years back when a few articles came out saying "some exercise is good but too much is bad for the heart".
One of the studies did have them exercising but they had an average age in the 60s, and the participants already had heart disease. That's not a good starting point. A better designed study would be a prospective one where you started at a much younger age, made sure all participants were of similar good health (i.e., cardiac disease ruled out), and then kept measurements of their actual exercise and how much intensity was involved. That study has not been performed, that I am aware of.
This leads me to the second problem with these studies. One of these big studies involved a questionnaire and then follow up for a decade (I think.......I'm on my phone so it's not so easy for me to go look this up again right now). The age range for this group was broad (I believe 20s to 60s) and the participants were the ones who judged the intensity of their exercise, not the researchers. The participants were asked about their exercise intensity and the researchers determined who developed a heart rhythm disturbance among the participants. Questionnaires are notoriously fickle with a lot more limited reliability. Also, as I believe an editorial about this study pointed out, what is considered to be intense exercise to a 20 year old is a lot different than to a 40 year old or 50 year old.........so again, self assessment and not true physical measurements by the researchers.
This may not have helped answer your question but I hoped to add a little perspective as to where the "exercise can be bad for those over 40" came from. Until better research becomes available, the jury is still out.
For me personally, I was paranoid and went to see a cardiologist. I told the heart doc "listen, I'm being VERY paranoid but I've seen too many men, who look very physically fit like me, drop dead at races". I've had to perform CPR in the middle of a race. He smiled, said he appreciated my honesty as to why I was there, and then proceeded to do testing. I had an EKG that day, wore a 24 hour holtor monitor to look for any aberrant rhythms, and had an echocardiogram done to check my heart. No, it's not fool proof but it did give me SOME piece of mind knowing I did not have an unrecognized heart rhythm disturbance and my heart did not show abnormal valve function, abnormal cardiomegaly, or other structural abnormalities.