Running marathons and other extremely debilitating forms of exercise increase the likelihood of cancer through the release of free radicals. Running as a form of exercise is extremely tough on the knee joint, even for someone who has no history or inherited condition.
So if you don’t think running is good for you, that’s fine with me. But I’ve already accomplished 45 years of running since I was in college. So your advice is a little late coming to the party. I’ve met people like you over the years who were anti-running but they didn’t have an answer for themselves as an alternative that worked any better and didn’t cause its own health or medical problems. Your bias shows in your description of running as extreme and debilitating. It is neither. Yes, I ran for 45 years until my knee cartilage wore out but all of my four siblings and my dad had the same condition and had knee replacements in their late 50’s and early 60’s too. None of them ran or exercised except me. So to blame the problem strictly on running is disingenuous. Genetic inheritance is the primary factor in my family. I’ve studied nutrition and all aspects of running for years, and I’ve never read anything that suggested I was more prone to getting cancer because I ran. Maybe there is some anecdotal evidence of this but it is not a prevalent opinion.
The positive benefits of running far outweighed the negatives. My doctors are all in agreement that I was much healthier and better off because I ran than I would have been if I hadn’t. My weight stayed normal, I was heart healthy, my pulse rate was down in the low 40’s and I felt strong and fit and never was sick for over 45 years. I started running in the late 60’s, because I was overweight and the Air Force required me to run a mile and a half to pass their fitness test. Over the years, running has become commonplace and is very popular today and millions of people participate in it for exercise. Running has the usual naysayers like yourself. It is easy for some to criticize others who have actually accomplished something in their lives but much harder to be out there on the field of play day in and day out, doing what they think will improve their lives.