Man aint that the truth. I am 54 and picked up bicycling recently after several years of a desk job and sedentary living. I got fat, my cholesterol is up, and my blood pressure is up. When I was in my 30's and in good shape I went to give blood and my resting heart rate was 38, now it's in the 80's. I used to ride centuries. When I first started this time I was just going to ride 10 miles, but I couldn't do it. I started riding by time doing 30 minutes, 3 days on and 1 day off. Yesterday I decided to do 40 minutes and I thought I was gonna die! It was so hot and humid. I actually had to stop and lay down in somebody's lawn for a few minutes. It was never this hard before.