Injuries, surgeries and setbacks are no fun, but it doesn’t always mean that you’ll turn into a blob, ending up with muscle atrophy.

Losing muscle depends on your prior health and activity level and the amount of muscle mass that you previously had. If you have an upcoming surgery, getting in better shape is always a good idea. But you can start to lose muscle in as quickly as one week of inactivity, or fully immobilized. The loss of muscle is known as sarcopenia.

Lean tissue is muscle that our bodies use to store nutrients, provide strength to our frame, and drive our metabolism. Skeletal muscle is the most adaptable tissue in our bodies, and is remarkably remodeled with a regular resistance exercise program.