Nice post from Steve Magness and Brad Stuhlberg, the guys behind the Science of Running site and podcast (and a variety of good books).
Thanks for sharing, Adam! I especially liked “Rule #4: You lose what you don’t train”. Great reminders.
Yeah, I keep reminding myself about the principle of adaption. You need to train in specific ways to get your body to adapt to the stress such that those particular actions become easier. That Rule #4 is a good reminder of why stopping a particular exercise can result in the body adapting back to not being able to do it well.
And it’s also worth remembering that doing the same exercise all the time means that the body adapts to that stress… and then stops. Nothing more is necessary. So if you just run 1 mile at 8-minute pace every day, that will get easier and easier, but that doesn’t mean you’d either be able to go faster or longer more easily (beyond a base of level of improved fitness, of course) without changing the stress.