We lose muscle and strength (and vo2max, coordination, response time, power, and more) as we age: a use-it-or-lose-it issue only or something more? … “use it or lose it” is certainly a thing. It applies to everything and always has, but we lose function faster now and its harder to get back now…so we have to be more mindful of maintaining everything we want to keep.
But how to fit it all in? How little is necessary to build and how long between session is tolerable? How to sequence activities to minimize interference? How to improve recovery to allow more to be done?