I listen to my own personal energy level ie I almost never stop because I have a lot of healthy energy. I listen to my body and right now have some lower back pain, so have already been out on my bike, to keep my pelvic area mobile.
My back pain under control without drugs so my aim today is to move as much as possible and to make the movements effective ie squats to strengthen the back muscles, which support my spine. I can do squats every time I lower myself to clean lower windows, lift full length blinds, clear under my bed etc
Life, my life, will never be wasted by sitting and doing nothing, the exception being if my body tells me that I need some rest.
I do jobs in the loft, balancing on struts, not long ago fixed two minor leaks in the soil vent pipe and then insulated it. It was too high and I am short, so did the job by doing `rock climbing` chimneying up two struts
I dig and look after my whole house and garden myself, am very capable and have lately got myself on a list for a local allotment. I might be 76 but have good strength in my body, through lifting heavy compost bagsetc
No way am I going to droop in a corner, waiting to get old. How I age is up to me