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.
With a first-time injury, proper care and sufficient healing time before resuming activity should prevent permanent disability. How long does a hamstring injury take to heal? The average healing times are: (1) mild strain â 2 to 10 days, (2) moderate strain â 10 days to 6 weeks, (3) severe strain â 6 to 10 weeks.The complications listed above are more likely to occur in the case of repeated injuries.amstring strains are of three types; 1  A mild or (grade I) strain, which is a slightly pulled muscle without tearing of muscle or tendon fibers. 2  There is no loss of strength. 3  A moderate or (grade II) strain, which is a tearing of fibers in a muscle or tendon or at the attachment to the bone. 4  Strength is diminished.