I work at a gym, teaching 5 group exercise classes per week. I teach yoga, water aerobics, and senior fitness. Besides those I teach, I also take classes there from other instructors. I get in about 3-4 spin classes per week, 2 core classes, 2 yoga, and 1-2 weight lifting. Each is an hour, but once a month we have a 1.5 hour spin class on Saturday morning. Special holidays we might offer a 2 hour spin! I get plenty of exercise and never have a problem sleeping well at night. BTW, next birthday I will be 60.
I'm glad to see so many of our board members walk and keep fit. Walking (not strolling) is a great way to stay in shape. It keeps your muscles toned, your weight in check, and your stamina up. Good for you!