Falls are potentially fatal. Falling is a skill. If able-learn it. Get comfortable on the ground, one day you may end up there with no one to help you. The blue print provides a means to train the reflexive response to prevent a fall as well as the strength and technique for self rescue.
Why not get a bunch of miles out of the way early and then go real slowly during the heat of the day. But there is a better way.
Mike has learned not to fear movement, but engage in it. Part of aging is not weakness and decline. We are always meant to be strong during all phases of life. Like others who have decided to act, Mike has observed that OS is not an exercise, but a simple life maintenance program.