I wish I’d had the discipline at a younger age to join a gym. I’ve done that now & am pleased at the results. I guess it was easier after retirement. Time is always short when you’re working.
Get a medium to large dog as a personal trainer.
They generally refuse to let you take a day off, much less less than 3x/day.
I wish I kept riding a bicycle from my early life on. Last year I rode 2,800 miles and the year before that 2,500 miles.