How to train your body to eat itself
Evidence from cell culture and model organisms suggest that stimulating autophagy increases longevity.
It's a natural process called autophagy (literally “self-eating”), and it’s the body’s system of cleaning house: Your cells create membranes that hunt out scraps of dead, diseased, or worn-out cells; gobble them up; strip them for parts; and use the resulting molecules for energy or to make new cell parts.
Regular exercise is the most popular way that people unintentionally help their body to cleanse.
Working out actually damages your muscles, causing tiny microscopic tears that the body then rushes to heal, making the muscles stronger and more resistant to any further “damage” you might put it through.