Hamstring strength for runners

The benefits of strength training are well known for endurance runners. Improved running performance and reduced injury risk make strength training for runners a necessary or  at least recommended training schedule inclusion.

However despite the growing awareness of the benefits of strength training for runners, one of the common oversights I observe in gym programs for runners is the absence or reduced focus on developing strength of the hamstrings. I see this oversight occurring with program prescribed by health professionals, and also in home based DIY programs.

Developing adequate hamstring strength is often overlooked, with the glutes, quadriceps, and sometimes the below knee muscles (soleus and gastrocnemius) receiving more attention. However developing hamstring strength is very important for reducing running related injury risk and also for optimising performance.

I neglected developing hamstring strength for many years of my running. I credit a focus to improve my own hamstring strength as one of the things that helped me get on top of my persistent knee-cap (patellofemoral) pain.

The role of the hamstrings when running  (Why hamstrings are important)

Work by Dorn et al 2015 showed that peak muscle forces generated in the hamstrings were up to 8.95 x body weight when running at speeds of 8.9m/second.

Interestingly the hamstring peak muscle force was high even at slower running speeds (3.49m/second).

As a runner runs faster the hamstring peak muscle force increases.

The above image sourced from @tendinopathyrehab Instagram account (Dr Peter Malliaras) and Dorn et al’s 2012 research highlights that the hamstrings whether we are running slow or fast, are working hard!

Our hamstrings play a role in generating force and stabilising/controlling our body when we run.

Many people mistakenly believe that hamstrings are not involved with endurance running but more so with sprinting. In actuality a runner’s hamstrings have several key functions during running irrespective of speed.

The ‘general roles’ of the hamstrings (2) when running are to both extend the hip (such as when pushing off) and fex (bend) our knee. Specifically the roles of the hamstrings when running include:

1. Force production when pushing off: the hamstrings play a very important role in pushing against the ground and developing force with the push off phase of running. The gluteals are also involved in this force production, with two-thirds of power coming from the glutes and one-third from the hamstrings. Hence strengthening both the glutes and hamstrings together when doing exercises is important.
2. Controlling the slowing of your leg with swing through phase of running. When the leg is swinging through the air prior to making contact with the ground the hamstrings are under a lot of strain. In fact this is the portion of the running cycle when the hamstrings are under the most tension. The hamstrings are trying to slow your shin from ‘flying off your thigh’-with an eccentric contraction, and trying to help the leg be pulled down towards the ground.
3. Energy transfer to the calf (gastrocnemius) below the knee occurs with the swing phase of running. This energy transfer pre-activates the calf and stores energy there prior to making contact with the ground.
4. To assist with resisting the collapsing of the knee when impact with the ground is made. When ground impact is made the musculature around the knee (quadriceps, hamstrings, and gastrocnemius) all need to synergistically contract rapidly in order to stabilise the knee and control the amount of knee flexion (bend) occurring underneath the body weight of the runner. This contraction allows for maximum use of the energy that has been stored at impact in the achilles tendon through the stretch shortening cycle. Endurance runners can become very quadriceps dominant for this control of the knee , creating a potential overload on the knee anteriorly with possible injury onset (eg patellofemoral pain).
5. Place the foot at ground contact. If you are a runner who over-strides you will use your hamstrings more than a runner who has their foot landing underneath their knee. The hip will move through a greater degree of active extension meaning the hamstrings will work hard to pull the foot back underneath the knee at impact.

Of an interesting note is that the hamstrings do not play any role in bending (flexing) the knee and bringing the heel close to the bottom during the swing phase of running. When the heel does make its way towards the bottom there is little involvement from the hamstring.

Hamstrings and fatigue

Furthermore, it is important to note that the hamstrings become more active as we get fatigued. As a runner gets fatigued they find it more difficult to control movement and generate force. As fatigue sets in muscle recruitment patterns change and hamstrings are called ‘upon more’. Hence there is a high reliance on hamstrings to function optimally when a runner is most fatigued.

The link between hamstring training and injury risk

A 2019 systematic review (3) and meta-analysis was performed to determine whether doing the nordic hamstring exercise (see below) as part of injury prevention exercise sessions would lower the risk of hamstring injuries.

View Nordic curls below:

The researchers discovered that exercise programs that included the nordic hamstring exercise in training, resulted in 51% less hamstring injuries.

This reduction in hamstring injuries was found across all athletes competing at different levels of competition across multiple sports: AFL, rugby union, soccer, and baseball.

Nordic hamstring exercise protocols varied across the 15 studies that were included in the review. One of the more common prescriptions of the Nordic hamstring exercise was: 3 sessions per week of 12, 10, and 8 reps, or 3×6-8, or 8-10 reps.

Another popular prescription was one session per week of 1-2x 5reps, performed across a season.

Quantifying hamstring strength

Quantifying hamstring strength can be done via the following ways:

1. 8RM max in a gym setting.
2. For example performing single leg prone hamstring curls and finding the resistance (load) at which 8 repetitions can be performed with good control. This can be done with a health professional’s help, or a gym buddy, or even by yourself.
3. Using a hand held dynamometer in a clinic. This would be performed by a trained health professional. I have not found great accuracy performing hand held dynamometry for hamstrings in clinic. The movement is not isolated and the force produced by the tester to counteract the force of the athlete can bias the score achieved. The athlete is instructed to pull the heel maximally towards their bottom (make test) or to resist the force of the tester attempting to push the heel towards the ground (break test).

See below for a video from Aspetar Sports Medicine Clinic of using the handheld dynamometer to assess midrange hamstring strength:

Outer range hamstring testing can also be performed as shown in the below video:

3. Nordbord testing. Testing with a device such as the Vald Nordbord is the current gold standard assessment for hamstring strength. To learn more about using the Nordbord for hamstring testing read the below and view the below video:

Hamstring strength testing: the Nordbord

The Nordbord provides accurate scores of peak eccentric forces produced when performing a nordic exercise, and provides data on both sides.

See below for the displayed data from a Nordbord assessment of my own hamstring strength:

4. Hamstring bridge assessment: to view the hamstring single leg bridge test see video below:

Interpretation of your scores is as follows:

• <15reps (poor)
• 15-30reps (satisfactory)
• >30reps (excellent)

Even in the absence of hamstring strength testing, a runner can begin performing strength work for their hamstrings.

The below section will outline some hamstring exercises that can be performed.

Exercises to strengthen the hamstrings

Exercises to strengthen the hamstrings should aim to assist with force development for push off, iron out any imbalances that may exist with the opposing quadriceps, and minimise injury.

Exercises need to focus on being able to tolerate high loads for long periods of time with the hamstrings in a lengthened or outer range (‘extended’ on stretch) position.

Here is a series of hamstring based exercises I like to prescribe for runners. Exercises can further be divided into capacity building, strength, rate of activation, and drill based exercises.

Hamstring exercises are shown below:

The exercises are as follows:

• prone hamstring single leg curls: curls heel towards bottom with control. Ultimate target is 0.3 x body weight for 3x8reps. Build up to this by starting at 3x12reps at a challenging weight.
• bench bridges single leg: progress by taking hands from side of body to across chest position 3x12reps
• bench bridge ups: push up through the back of the heels (progress by taking hands from side of body to across chest position) 3x12reps
• single leg romanian dead-lifts (start with 3x12reps and build towards 4x8reps with heavier loads: use kettlebells or dumbells)

Other exercises that can be performed not in the above video include:

• single -leg back extensions below:

Compound exercises such as: deadlifts, squats, Nordics curls, and variations of Nordics.

Summary

Be sure to not neglect to strengthen your hamstrings as part of your strength and conditioning program. Adopt several of the above listed exercises into your strength & conditioning program.

Related

Strength & conditioning for endurance runners podcast featuring Richard Blagrove HERE>>

Physio With a Finish Line™,

Brad Beer (APAM)

APA Titled Sports & Exercise Physiotherapist (APAM)
B.Physio/ B. Ex. Sc
Author ‘You CAN Run Pain Free!’
Founder POGO Physio
Host The Physical Performance Show

Featured in the Top 50 Physical Therapy Blog

References:

(1) Schache AG1, Dorn TW, Williams GP, Brown NA, Pandy MG.Lower-limb muscular strategies for increasing running speed.J Orthop Sports Phys Ther. 2014 Oct;44(10):813-24. doi: 10.2519/jospt.2014.5433. Epub 2014 Aug 7.

(2) Blagrove, Richard (2015), Strength & Conditioning for Endurance Running.

(3) van Dyk N, Behan FP, Whiteley R. Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries: a systematic review and meta-analysis of 8459 athletes. Br J Sports Med Published Online First: 26 February 2019. doi: 10.1136/bjsports-2018-100045