My main health challenge is getting enough sleep. I'll see how days off affect that. The effort does vary considerably with other conditions. This week I easily caught up to another rider, and it turned out to be a younger guy who is locally famous for riding 40 mile loops. I don't know if we could ride together. I paired up with another rider on a tour to help with drafting, and he was used to a gentle warm up. I was used to sprinting to work in the morning. I had to ride my brakes for the first two miles, and then we matched for the rest of the day.