Commonwealth Sports Medicine

The words “PULLED HAMSTRING” may send a chill through your body as you recall the pain, time off, and frustration of a previous injury. In fact, hamstring strain is one of the most common running injuries. Preventing this common injury is easier said than done. Recovery from hamstring strain requires a bit of knowledge.

ANATOMY

The hamstring muscle group consists of three muscles (biceps femoris, semitendinosus, semimembranosus) that originate on the ischial tuberosity (sit bone) and inset on the 2 bones of the lower leg. Hamstring contraction causes the knee to bend and the thigh to swing backward- 2 important motions in running and bicycling.

Muscle strain is typically divided into 3 degrees of severity:
1) A grade I strain is mild. Only a few muscle fibers are disrupted. There is a bit of pain and swelling, but the muscle remains strong.
2) Grade II strains involve larger partial muscle tears. The tear results in some strength loss.
3) With a grade III strain there is a complete tear of one or more of the 3 hamstring muscles. This severe injury and is quite disabling.

PREVENTION
Avoiding “TOO MUCH TOO SOON” is key to the prevention of hamstring strain. Typical culprits of this injury are 1) increasing mileage by more than 10% per week (remember to obey the 10% rule), 2) too much speed work or down hill running, and 3) tight muscles. When we run sprints or down hill, our hamstrings work overtime, trying to slow us down while in a stretched position. This simultaneous contraction while stretching is called an “eccentric contraction.” Eccentric contraction exercises should always increase GRADUALLY; if not, injury will ensue.

In the medical literature, the jury is still out about weather or not stretching can actually prevent hamstring strain. Some studies conclude that stretching helps while most say it makes no difference. Most of these studies do not have their subjects perform adequate stretching. In other words, for hamstring stretching to possibly be effective, it must be done correctly, held for at least 20 seconds and repeated frequently though out the day.

TREATMENT
What if it’s too late… you’re already suffering the deep ache on the back of your thigh… wishing this article had been out a month ago. Hamstring strain frequently recurs and becomes chronic. So proper treatment early on is essential. Take a visit to your health care provider in order to get a correct diagnosis and to coordinate treatment.

Treatment of muscle strain is divided into several stages, which coincide with stages of muscle healing. Initial rehabilitation is designed to decrease pain and inflammation. Next, a couple of weeks are dedicated to stimulate collagen healing. Maintaining fitness during this stage is easy for the mutli-sport athlete who can replace running with other sports. Of coarse the rate of progression through rehabilitation depends on the severity of the strain. The rehab process continues for several months, keeping muscles strong to avoid reinjury.

Stage I, Week 1:     decrease pain and swelling     P.R.I.C.E.: Protection (walk with crutches if limping to avoid other injuries);     Relative Rest (if it hurts, don’t do it); Ice (a bag of frozen peas and an ace wrap works great);     Compression (the ace wrap); Elevation (higher than your heart).
Stage II, Weeks 2 to > 3: control pain, align and strengthen new collagen, maintain conditioning with submaximal strength exercises; bicycling without clips or straps (to avoid vigorous “pulling up” on pedals); swimming with pull buoy.
Stage III: Weeks 4- 6: maintain strength and flexibility, increase eccentric strength Stretching; strengthening; jump rope; light jog; run

Return to more normal workouts may ensue when:
1) Pain is gone.
2) The strength on the injured side is 90% that of the normal side.
3) Flexibility and coordination are normal
With return to full activity, any hamstring tightness should be a warning sign that perhaps workouts were begun too soon. Talk to your health care provider again to re- evaluate and perhaps rewind the rehabilitation.

Happy Trails!

-Dr. Stadler