Yesterday, I spent roughly 3 hours over the course of the day shoveling 24 inches of snow. DH helped some. At the end of the day the muscles in my upper back felt worked to exhaustion, and my weak right knee (the one with but a token anterior ligament left) began to wobble.

However, this a.m. I awoke and felt fine. I'm in better shape now than I was in my thirties or forties!