Use it or Lose it
The “Principle of Use or Disuse” implies that your exercise gains will go away when you do not maintain them. This means that you become deconditioned and muscles atrophy when not in use. Muscle strength tends to go away at about 1/8 of starting strength per week, with larger and stronger fast twitch muscle fibers decreasing in number earlier than slow twitch fibers. Functionally, slow twitch or postural muscle fibers can “turn off” in eight hours while sitting or laying down and must be “prompted” to regain normal capacity. Over time muscles become shorter and less limber with disuse. When we move, gravity forces our muscles to contract and pump blood back to our hearts. It’s also easier to breathe since our postures tend to be better when exercising. Exercise stimulates our metabolism, the formation of new bone cells, improves glucose tolerance and gives us an overall sense of well-being. So enjoy every step, rep, set, lap or mile. Know that it’s worth every minute.