Running Injury Spotlight: Hamstrings

Hamstring strains and injuries are most often associated with sprinters and soccer players, however the use of hamstrings in distance running should not be overlooked. Hamstring strain injuries (HSI) frequently cause a significant loss of time from sport and have high rates of re-injury. In fact, those with a history of HSI have a 3.6-times higher risk of sustaining a future HSI. Studies suggest that these re-tear rates may be due to inadequate rehabilitation or premature return to sport.

Anatomy

The Hamstring muscle group can be found on the back of the upper leg/thigh region (opposite the quads).

There are 3 muscles that make up the Hamstring group:

Biceps Femoris
Semitendinosus
Semimembranosus

Say that 3 times fast! The hamstring muscles cross two joints, the hip and the knee and therefore help to extend the hip and flex the knee with gait (running and walking).

Because the hamstring muscle groups is usually perceived to be “tight”, runners generally tend to spend time stretching those tight hamstrings and neglect the strengthening aspect. Hamstrings are an essential muscle group in distance running, and failure to properly load the muscle properly, can lead to hamstring muscle belly strains and tendonitis, as well as a painful condition called proximal hamstring tendinopathy (where the muscle group attaches to the sits bone).

Fast Facts:

It is believed that the hamstring muscle group has a higher percentage of type II fibers (which are “fast” twitch) than other thigh muscles, making the muscle more susceptible to injury
The long head of the biceps femoris muscle is the most commonly involved hamstring muscle, likely due to the fact that this muscle is lengthened with an increased anterior pelvic tilt (all you runners with tight/weak hip flexors and core muscles), which anatomically places the hamstring muscle group on stretch, and potentially increases the likelihood of injury
Uphill running forces the hamstrings and glutes to work in a "“shortened” position, which allows them to fatigue quickly

Different Hamstring Injuries

Area in red highlights common pain points for each type of hamstring injury.

Proximal Hamstring Tendinopathy:

This injury can be a pain in the butt… Literally. Often confused with glute or buttock pain, a proximal hamstring tendinopathy is an irritation of the tendon where it inserts on ischial tuberosity (sits bone). Aggravated with running, walking and repetitive knee flexion (bending).

Hamstring Strain:

Dull or achy pain within the hamstring muscle belly, usually caused by a traumatic injury to the muscle. This could be an over stretching, or tearing injury and can be acute (due to a sudden movement), or chronic (due to repetitive overuse).

Hamstring Syndrome:

Hamstring syndrome originates in the same location as hamstring tendinopathy, with the key difference being that hamstring syndrome involves the sciatic nerve. Therefore, runner’s experiencing hamstring syndrome will feel a shooting pain down the back of the leg, that is often exacerbated by the position of the lower back, and pressure on the sciatic nerve with sitting. The path of the sciatic nerve crosses where the hamstring tendon inserts on the sits bone, and can be further irritated by hamstring movement. Treatment of Hamstring Syndrome requires lumbar, core, and glute strengthening, as well as specific interventions to address nerve related symptoms and spinal position.

RISK FACTORS FOR HSI

One of the biggest risk factors for another hamstring injury, is a previous hamstring injury!

This suggests that incomplete rehab can be detrimental post HSI. After a hamstring injury it is important to continue with strengthening and progressive loading, EVEN when painfree. When we take a look at this list, numbers 4, 5 and 6 we can control for. If we strengthen the hamstrings, we can increase length of the muscles, along with strength (remember, long muscles are strong muscles!) We can also strengthen our abdominals, hip flexors, glutes and lumbar extensors to restore muscular balance around the pelvis, to decrease anterior pelvic tilt and promote a more neutral spine and decrease load on the hamstring. Lastly, we can LOAD those hamstrings, to strengthen them and decrease the risk for another hamstring. It is essential to incorporate challenging hamstring strengthening into a runners prehab routine to stave off irksome hamstring injuries.

PROGRESSIVE LOADING

A variety of concentric, eccentric and isometric exercises, involving heavy loading are critical to building a healthy, strong Hamstring muscles and tendons.

As the hamstrings are challenged at a variety of angles during running, especially when running uphill, it is imperative to train, strengthen and challenge the hamstrings throughout these different ranges. Simple banded hamstring curls are seldom enough of a challenge to mimic the high demands placed on the muscle group with running. Each patient and runner is different, however our general progression through hamstring rehab and strengthening is outlined below.

THE BASICS: Hamstring Loading Progressions

Hamstring biased bridges are a great place to start with hamstring rehab. By digging the heels into the ground vs the full foot, we can bias those hamstring muscles to work a bit harder. As seen in the video, it is important to challenge the hamstrings at a variety of angles in order to activate all portions of the muscle. Also pictured above are bridges with sliders which allow for ECCENTRIC strengthening of the hamstrings. Eccentric strengthening means strengthening while the muscle is lengthening. This is a nice way to get an active stretch of those muscles while also working on strength as the muscle lengthens.

FUNCTIONAL/ECCENTRIC EXERCISES: Progressed Hamstring Loading

Though bridges are an excellent way to target and isolate the hamstring muscles in a controlled position, they are not super functional, or translate well into everyday life. The next step in hamstring rehab is to continue to challenge those muscles in more difficult positions, such as standing and half kneeling to better mimic everyday tasks— think deadlifts and more eccentrics! This exercises are more difficult, and require greater coordination of a variety of muscle groups in conjunction with the hamstrings.

PLYOMETRICS

So we have strengthened those hamstrings in advanced positions—- now what? If you are looking to get back to activities that require fast powerful movements such as running, hiking/climbing, court sports and heavier lifting, plyometrics are a vital piece of performance training that are often neglected in “incomplete rehab” scenarios. It increases our springiness making us more economical, powerful and resistant to injury. We need to make sure the hamstrings can tolerate these more powerful single leg movements.

BIG TAKE AWAYS

Hamstring strengthening is often under prioritized in distance runners, but is essential in running gait (especially with hill running!)
Hamstring injuries are often recurring, which means FULL and COMPLETE rehabilitation (that includes advanced total body challenges and plyometric drills) is essential in staving off future injury
Hamstrings need variety in strengthening challenges: this means exercises at different angles, on a single leg, in supine, kneeling and standing
Do not forget the role of pelvic position (and therefore, a strong core) on hamstring length and pull!
No hamstring pain? The best rehab is prehab! Start adding some of these hamstring challenges to your strength routine and avoid an angry hamstring in the future.