Without proper nutrition, hormones, and rest, your body will not be able to repair damaged muscle fibres.

• Protein in our diet preserves muscle mass. It provides the building blocks for new tissue in the form of amino acids.
• Hormones such as insulin-like growth factors and testosterone shift the body into repair and growth.
• However, this repair mainly happens when we're sleeping.

When your body has adapted to an activity, it won't produce enough stress to stimulate new muscle growth. 

• Hypertrophy, an increase in muscular size through exercise, is possible by exposing your cells to higher workloads than they are used to.
• If you don't c...