1 Collagen is most commonly found within the body in the skin, bones and connective tissues. 2  The word collagen is derived from the Greek kolla, meaning glue. 3  Collagen gives the skin its strength and structure, and also plays a role in the replacement of dead skin cells. Collagen is most commonly found within the body in the skin, bones and connective tissues. 2  The word collagen is derived from the Greek kolla, meaning glue. 3  Collagen gives the skin its strength and structure, and also plays a role in the replacement of dead skin cells.
Healing time depends on the severity of the strain. Mild muscle strains usually heal within two weeks. Moderate muscle strains may take six to eight weeks to heal. Prevention of Recurring Back Strain. Many people who experience recurring back pain have weak core muscles - the muscles that support the back.
if you are injured take the time needed to let the muscle heal before you return to sports wait until your muscle strength and flexibility return to preinjury levels this can take 10 days to 3 weeks for a mild strain and up to 6 months for a severe strain such as a hamstring strain