Up until my late 50s I was an avid 5-miles-of-street-and-hill runner. I enjoyed it immensely but had to quit due to nerve damage in the lower spine (lumbar region). And the number one reason I ran was that I simply enjoyed the hell out of it. Plus, there's nothing quite like "runner's high." The nerve damage became so severe that, at 81, I could no longer walk. But, no excuses -- now, at 83, I still do between 50 and 60 miles per week on my stationary bike. And for the calendar year 2023, I am averaging just over 600 pushups per day (really!). Why? Because the bike and the pushups are my only 2 options. So since that's what I CAN do, it's what I Do do. And nerve damage aside, I'm in excellent health, haven 't had so much as a cold in years (more than 10, I think), have great life habits, a wife and dog that both delight in spoiling me, so I should be around still for several years to come. By the way, I'm a great fan of your articles, Dr. Michael. Keep writing and I'll keep reading. Thank you! Ciao!