Boy, I sometimes feel a lot older than I actually am. I'm trying to get some exercise, I walk almost every day on the treadmill anywhere from a half to a mile, a lot of times more than once a day. I also carry 5 pound "Barbells" when I am walking and I do arm curls and full arm lifts with them in my hands. Don't sound hard, but do it for about 20 minutes at a time at about a 3.2 to 3.5 mph pace. It gets TIREING!