HAMSTRING INJURIES

Hamstring injuries happen mostly in short running distances and sprints. Nevertheless it is a common injury for long distance runners as well. Anatomically the hamstring muscles are representing a group of muscles of the posterior thigh, consisting of the biceps femoris, semitendinosus, and semimembranosus. Hamstrings are major extensors of the hip and strong flexes of the knee.

Biceps femoris is the most lateral of the three hamstring muscles. It has a two-headed muscle with the origin of its long head on the ischial tuberosity, and the origin of its short head on the linea aspera and distal part of the femur. It has a common insertion onto the head of the fibula and the lateral condyle of the tibia. Contraction of the biceps femoris extends the thigh and flexes the knee, and enables lateral rotation of the leg, especially when the knee is flexed.

Semimembranosus is the one of the three hamstring muscles which lies deep to the semitendinosus muscle. The semimebranosus has its origin in the ischial tuberosity and its insertion on the medial condyle of the tibia. Its actions include extension of the thigh on the hip, flexion of the knee, and medial rotation of the leg.

Semitendonosus lies medial to the biceps femoris. The origin of it is on the ischial tuberosity(in common with the long head of the biceps femoris) and its insertion is on the medial aspect of the upper tibial shaft. The semitendonosus extends the thigh at the hip; flexes the knee; and, with the semimbranosus, medially rotates the leg.

So why are these strong muscles injured, especially during fast run? There are two major biomechanical reasons for it, from the Pose Method point of view. First one is related with the late pull of the foot from the ground, when the foot lags behind. In a slow run the late pull is not a problem, because it is possible to compensate for this mistake by slowing down falling forward or by using hip flexors (wrong muscular involvement, but could work for a certain level of speed). But when the speed goes up or fatigue increases, compensation for this same mistake becomes more strenuous and hamstrings become overworked. It brings even more hamstring fatigue, and soreness, which finally leads to overuse and injury.

As you remember, the main reason for pulling the foot from the ground under the hip is to reproduce the Pose in order to fall forward. So when the swing foot is not under the hip, while the other foot is on the ground, the runner subconsciously tries to compensate for this delay and uses a powerful front muscle of the thigh to pull the leg forward. It happens simultaneously with the work of hamstrings pulling the foot under the hip. Front muscles are stronger than posterior one, so they pull the thigh forward.

This movement of the thigh forward and the foot under the hip creates a discrepancy between the speed of the thigh and the foot, which applies to the hamstring muscles. So this is the second biomechanical reason of hamstring overloading. After this the only question remains: to which muscles exactly does this overloading go. It depends on direction of the foot and thigh movement (inside-outside), their speed, foot orientation, etc.

Therefore, in order to avoid this injury we need to eliminate these reasons. First of all, do not be late with pulling the foot from the ground and do not hold the foot (leg) behind. At the moment one foot touches the ground, the other foot should be under the hip in the Pose stance ready to start falling forward immediately. To perfect this action we are using lots of pulling exercises. One the one hand, they strengthen these muscles, and on the other, they develop our perception of the pulling action incorporated with the body falling forward. There is no faster pull, but only on time with the runner falling forward.

Another way of injury prevention is to reduce muscle activity of hip flexors and quads in pulling the thigh forward (the so called, knee drive forward) in order to avoid the conflict between the front and rear thigh muscles.

The treatment of this injury, if you got it, goes through several stages, depending on the seriousness of the injury. Read more about it in Dr.Romanov's Training Essays Vol.I - a collection of short articles written by Dr.Romanov on various training, exercise and rehabilitation topics.

Dr.Romanov