I'm almost 70 and ride daily, between 35 and 50 fairly hard miles. When I get done with my rides my legs are often tired. Every once in a while, they actually do hurt. At one point, I would put them under an electric blanket for a little while and that seemed to help quite a bit. Unfortunately, you can only keep your legs under an electric blanket for so long. So I started doubling up a regular blanket and putting it on the bed over the area where my legs are at. I do this on top of any other blanket we may have on the bed. The idea is to keep the legs warmer than the torso for the eight or so hours you sleep. Next morning, the legs are ready to go and feel as if I've never ridden a bike at all. I've been doing this now for several years and it works like a charm. Since my wife also rides, she does the same thing and her legs are always ready to go the next morning.