Having seen the way you look in not-too-old videos, you look overweight, and your upper-body looks rather weak. That makes me fear for your life expectancy. I love your work, and it may be crucial that you don't stop cold until at least your eighties.
Of course, getting in good physical shape won't be easy. It takes time, and may even slow down your work, at first. But you may want to seriously consider the long term trade-off.