Sandy, working in the yard / garden is a great workout. Not quite the same as running, but takes energy and requires yummy food afterwards!
I've been out in our jungle doing initial rough pass weeding for the year (yes, year), and I can bear witness to the exhaustion! Hard to make myself go back out ... but getting close to 'done', so I've got that going for me.
I just wish I had an easy solution for what to do with everything I pull up or lop off. I hate putting it out as trash but I think I may have to start. There's just too much of it.
Only a little bit left to do.
And definitely agree with the yummy food afterwards!