When I turned 70, my primary asked me about my exercise. I told him I walked, danced tango, swam and did pilate once a week. He looked at me and said, that's not enough. I want you to do strength training twice a week so you will be strong going into your 80's. I am 80, do strength trining with a trainer twice a week, swim once a week often with a trainer, walk, take 4 flights of stairs at least once a day in my apt bldg.