Age is in your mind
When I was 18, I thought 33 was old. At age 33, I thought 50 was old. Now at 65, I don't know what old is unless one cannot cum and have sex of some sort.
Maybe I'm just lucky but still have sex with my wife at least once a week but also masturbate two or three times a week and every orgasm is as good as when younger if not better. No longer cum in three minutes so sex with wife is a half hour to well over an hour and much more satisfying for both. Or masturbating, if pressed, can cum in five minutes I guess but prefer a long leisurely session by myself but usually with my wife who will massage my balls or when really intense, will fuck my ass with a slim vibrator as I jerk off to one super orgasm.
More than one doctor has told me to use it or loose it and many male friends have lost it by my age. Usually to the chagrin of their partners. In addition to feeling great, it's healthy for men and helps ward off prostate problems later in life. Keep jerking and cummin guys. It's all positive not to mention feel good and fun.