Torn Hamstring Again?

By Benita Kropman B Sc (Physio)

Chronic hamstring niggles are very common amongst endurance runners and are often very difficult to solve. Most of the time the injury appears from nowhere and does not show up on any ultrasound scan or MRI.

It is important to understand the role of the hamstrings and particularly the Biceps Femoris, in order to understand the cause of these frustrating injuries.

In general we can consider the Hamstring as the ‘speed-muscle’ whereas the Quadriceps will be the ‘hill-muscle’. Athletes with stronger hamstrings (posterior line) on the Bunkie Test will normally admit that running fast on flat surfaces is their forte, where runners with stronger Quads (anterior line) normally prefers a hilly run to a flat run or a downhill run.

The Biceps Femoris plays most certainly a big role when it comes to fast running and speed training, but it is also part of the very important spiral line in the body. Every functional movement of the body always includes some form of rotation. When we run, the left shoulder moves forward together with the right hip, while the opposite shoulder and hip are responsible for the driving force by moving backwards. If any of these 2 rotation patterns becomes locked in a way that it prevents the opposite pattern from functioning, the strain will immediately show up somewhere in the body.

The rotation pattern in running involves the following muscles:

When the R Lattisimus Dorsi contracts, it rotates the R shoulder backwards and downwards. Through the fascia (connective tissue) connection, the contraction continues through the thoracolumbar fascia towards the L hip, linking up with the Gluteus Maximus, the huge muscle, which extends the hip and together with the Biceps Femoris drives the body forward, whilst rotating the hip outwards. At the same time the anterior upper spiral sling causes a contraction of the L External Oblique and the R Internal Oblique, pulling the R hip forward. The contraction then continues through the Tensor Fascia Lata and Gluteus Medius and Minimus, which rotates the R hip inwards and at the same time stabilizes the body.

Once the Gluteus Maximus and Biceps Femoris reach full contraction, the whole pattern reverses to allow the opposite spiral pattern to drive the opposite leg backwards.

If both these patterns are balanced and aligned, the muscles are able to move through full range without any fascia restrictions and the runner will have no difficulty with speed training or hill repeats.

A soon as the endurance runner decides to do speed training, the emphasis will fall on the driving pattern, which will result in strengthening of the pattern that includes the Gluteus Maximus and Biceps Femoris. While gradual progress in speed training will allow gradual strengthening of these muscles, overtraining of this pattern could cause the fascia layers to lock up around these muscles in order to add support, resulting in limited muscle mobility, whilst the opposing muscles, the Quadriceps (linear line), TFL, Gluteus Med and Min (rotation pattern) lock up in a lengthened position, causing weakness of these muscles. This leads not only to instability of the hips, but also to a lack of strength on hills.

When an endurance runner decides to do their speed training on the track, it creates a whole new scenario. Running around a track with the L leg on the inside, will cause the right leg to work harder and stride further, resulting in more inward rotation of the L hip and more outward rotation of the R hip. The Biceps Femoris, being a lateral rotator will therefor work harder for rotation as well as for hip extension and knee flexion, resulting in a shortening of the R Biceps Femoris. The L Biceps Femoris, being a hip external rotator, ends up in a lengthened position, due to increased medial rotation of the L hip. If the speed training is progressed too quickly, the fascia will lock to support the muscle and the L Biceps Femoris will end up in a vulnerable and weakened locked long position.

As soon as the athlete now leaves the track to continue at full speed in a forward direction, the spiral lock will cause dysfunction in the L hamstring resulting in a chronic niggle. Slow running might be bearable but due to the fact that the muscle is locked in a long position, it will not be able to contract with great force without pain and cramping.

Track athletes should not struggle with this injury, since the outer hamstring becomes conditioned to do more work. However, we do see the common hamstring pull when a 200m runner accelerates in the final straight, where both hamstrings are required to be able to contract fully, which then indicates that there is a locked fascia pattern, and most properly due to a too quick progress in training.

To conclude- if you are an endurance athlete, make sure you do your speed training in a straight line and not on a track, to avoid a spiral lock. If you are a 200m track athlete, it would be normal to have a stronger rotation and extension pattern on the one side, but make sure that your fascia is not locked in a spiral pattern, which could cause a crisis in the final 100m.

When we use the FROM assessment in the Lyno Method, it always give a clear picture of the client’s locked habitual patterns. The analysis enables the practitioner to determine exactly which habits and   patterns are responsible for the strain on the body. By using the fascia release technique in areas as indicated by the FROM test, locked patterns can be released quite easily, resulting in restored neutral movement and a better chance to perform optimally.