When will a muscle ligament strain heal? It depends on the severity of the strain and whether it was treated properly. Strains are classified as mild, moderate and severe. For mild strains, they usually heal naturally in 2-3 weeks because there is no obvious tearing of the fibers. For moderate and severe strains, because there is partial or even complete tearing of the fibers, clinical healing takes more than 3 weeks, with a minimum of 3 weeks. If correct treatment, such as timely immobilization after the injury, the initial clinical healing can be achieved in about 3 weeks, the cast or brace can be released for functional exercises of the lower limbs, and the injury can be firmly healed in about 3 months, and return to sports in 0.5-1 year. If moderate or severe strains are not treated promptly or appropriately, the optimal healing time may be missed, resulting in strains that do not heal on schedule.