Yeah, perfect. Of course you ride the climbs harder, hard enough to breathe rather heavily. Fine, all you need to do. Keep keeping on and watch the over-performers drop by the wayside with a-fib or whatever. The trick is simply to keep doing it.

There are two reasons we don't see all that many over 70 road riders or hikers: indolence and injury. As you get older (or right now, depending), you'll want to add 1 or 2 days a week of weight work to fight sarcopenia and bone loss and thus injury. Really important.