Lots of men are so beat up from physical injuries they suffered when younger they are limited in what they can do without pain. Knee surgeries, hip replacements, etc.
All those sports you did when young like playing football and wrecking your knees come back to haunt you.
For those who did not have injuries the combination of poor eating habits, lack of exercise, drinking, smoking, and years of sitting on their asses adds up.
My advices to those of you in your 30s and 40s is to keep training, eat smart, Moderation in bad habits like drinking, not smoking. Get enough sleep. Avoid sun exposure or use sunscreen.
Avoid activities that will beat you up and cause debilitating injuries. Skip the weekend warrior sports leagues where you could tear up your knee. It's not worth it.