A lot of wisdom here! I'm in my mid 50s and sometimes have lower back trouble. If I thought my lower back could take it, I would seriously consider leaving software engineering and switch to a trade.

Going to the gym is pretty different from doing manual labour, it's not really a solution.

That's true! I think the idea is more along the lines of 'do it on your own terms'.

Sure, of course it’s different. It’s much safer, you can get much more variety of motions and routines, you can take a day off or stop early if you need to, you can listen to a podcast, read a book or watch tv.

Manual labor is not just about getting physical exercise.

I go to the gym every day and take it very seriously, but it’s a different thing. Just like doing sudoku can’t take the place of an intellectually stimulating job.