Regular exercise is the best way to ease many "growing old" problems unless you have a specific injury or illness. Hard work wears us down so we don't feel like expending the energy to go for a walk (or run) or even to the gym to do some light resistance training.
But if you can find the energy to get started go to a gym and have a personal trainer put you on a program that fits YOUR abilities. The important thing is to keep our aging bodies moving - but doing it in a way that will not irritate old hips and elbows. Proper form is vital, thus the need for a trainer for most of us.
The old adage, "You have to expend energy to get energy." It certainly has proven true for me. I have taken to bicycle commuting to and from work. Getting there revs me up for the day. Coming home makes me cuss a little and I am totally wasted by the end of the day but I sure do sleep well. Following morning I am charged and ready to go.
Consider an exercise program.