Recently, a regular on our local group rides past away from a heart attack that he suffered during the ride. He was a very fit middle-aged man and I had just gotten to know him, it shocked me to the core. Anecdotally, this is the 4th endurance athlete I know of locally that suffered a heart attack and the 3rd to pass away from one.
Someone in our local group shared this video from Dr. James O’Keefe, a cardiologist with a personal background in endurance sports. You can see the video here. Granted the video is with reference to marathons, but I think it can apply to any endurance sport. In summary, he suggest that you should limit strenuous exercise to no more than 7 hours a week, especially if you’re over 40 years old. Given that his basis of non-strenuous exercise is walking, I would assume strenuous is anything over an endurance zone for cycling. In another video he suggests that shorter HIIT workouts are more heart-safe than long workouts at relatively high intensity, I would assume that would be something like sweet-spot or FTP.
I’ve heard about high-level endurance athletes having heart attacks and heart problems, but I guess I never realized that it also affects your average amateur cyclist too; it was like a gut punch. 7 hours a week is basically two 50 mile group rides, so does that just go out the window in light of this information? Do I go back down to low-volume training?
I plan on pushing my doctor to let me see a cardiologist, but has the effect of endurance training ever factored into your training plan and fitness goals? Prior to the recent events, I would have never thought I might be damaging my heart with endurance training.
EDIT: I should mention that I have a family history of heart problems. I started cycling a few years ago for heart health, but it has since morphed into a desire for a high level of cycling fitness.