Returning to the OP itself …
First, kudos for recognizing the importance of exercise and adding strength training to your life. Seriously. It is increasingly more and more established that little is as important as exercise, both aerobic and strength training, for increasing healthspan. Yeah things like don’t get shot, and don’t smoke are up there too … And you may be interested in @Dr_Paprika’s long lived thread!
No need to read the whole thing but lots there that may interest you.
Second. You are a mere pup of fifty and you are calling yourself “an old man”? Know the room kid!