In our third decade, we start losing mass in skeletal muscles, and in our forties, the process accelerates—we may lose as much as 10 to 20 percent. Climbers may note this less because the decline is greater in the lower body than in the upper. But still, it’s happening. Most of the muscle lost is fast-twitch, so power will drop first. But there is some good news: Endurance persists. Read on to sidestep nature.
Hate to admit it but I’m in that “third decade” group.