When a quadriceps muscle strain occurs during a competition or training, it is important to react immediately. In the 10 minutes following the trauma one needs to put the knee of the affected leg in 120° of flexion. This avoids potential muscle spasms, reduces the hemorrhage. If the knee is left in extension the healing process will be slower and more painful because the quadriceps will start to heal in a shortened position.
By placing the injured leg to rest the first 3-7 days after the trauma, we can prevent further retraction of the ruptured quadriceps muscle (the formation of a large gap within the muscle), reduce the size of the hematoma, and subsequently, the size of the connective tissue scar. Elevation of an injured leg above the level of your heart results in a decrease in hydrostatic pressure, and subsequently, reduces the accumulation of interstitial fluid, so there is less swelling at the site of the tear.
Prolonged rest causes more damage than good
During the first few days after the injury, a short period of immobilization accelerates the formation of granulation tissue at the site of injury, but it should be noted that the duration of reduced activity (immobilization) ought to be limited only until the scar reaches sufficient strength. This means that the scar is able to withstand the muscle-contraction induced pulling forces without re-rupture.
Rest prevents worsening of the initial injury, but you must not stay off the leg for too long. At this point, gradual mobilization is started followed by a progressively intensified exercise program to optimize the healing by restoring the strength of the injured muscle, preventing the muscle atrophy, the loss of strength and the extensibility, all of which can follow prolonged immobilization.
Ice or cold application is to lower intra-muscular temperature and decrease blood flow to the injured area. Compression may help decrease blood flow and accompanied by elevation to decrease both blood flow and excess interstitial fluid accumulation. The goal is to prevent hematoma formation and interstitial edema, thus decreasing tissue ischemia. However, a prolonged immobilization phase, will be detrimental for the quadriceps muscle regeneration.