Hamstring Strain in Runners – Causes, Treatment Options and Prevention

A close up of an athletes extended thigh while running, with a hamstring strain highlighted

A “pulled” or “strained” hamstring is an injury to one or more muscles at the back of the thigh. You will typically feel pain at the rear of your thigh muscle and might remember the moment you pulled the muscle – often accompanied by sharp pain and having to stop your workout. In this post we cover causes, treatment and prevention of hamstring strain in runners so you can return back to running quickly.

What’s the function of the hamstring muscles during running?

The three muscles making up the hamstring (Semitendinosus, Semimembranosus and Biceps femoris) are most active during the late swing and late stance phase. 

A rearview of a sketched athlete standing on a track.  We see the three muscles composing the hamstring (Semitendinosus, Semimembranosus and Biceps femoris) to illustrate this article on hamstring strain.

The hamstring muscles contract eccentrically (i.e. are lengthening while applying force) during hip extension to allow you to extend your leg behind during late stance phase. They also contract eccentrically during the late swing phase to achieve knee extension.

Most hamstring strains in runners occur when the hip is extensively flexed and the knee is hyperextended during the late swing phase. (1) This is likely to happen at a higher pace, i.e. during sprinting or interval work. 

Grades and Symptoms of hamstring strains

Hamstring strains are classified into 3 grades, according to severity.

Grade 1 hamstring strains are mild, as the muscle has “only” been pulled, with minimal damage to muscle fibers. Typically the muscle’s strength or endurance is largely unaffected and walking is possible pain-free. Grade 1 strains will still cause sharp pain at the back of your thigh and may make it difficult to move, however they tend to heal relatively quickly within 2-3 weeks.

Grade 2, “Moderate” hamstring injuries occur when there is a partial tear in the muscle. This will typically be accompanied by bruising and swelling at the back of your leg and normal walking may not be possible without pain.

Grad 3, “Severe” hamstring injuries involve a significant or complete tear of the muscle or the tendon that connects the muscle to the bone. Pain and swelling will be more massive and recovery will take several months. Grade 3 hamstring injuries are rare and often associated with a loud “popping” noise at the time of injury.

If you suspect to have a Grade 3 hamstring tear it’s a good idea to see a doctor rapidly. If you have a complete tear and need surgery (which offers excellent chances of recovery) then timely surgery will be easier to perform. In a recent study 96% of those who had surgery returned to sports, but complications for those receiving surgery later were higher. (2,3)

Causes of hamstring strains in runners

Risk factors for hamstring injuries include a previous hamstring injury. 60% of those who have a hamstring injury will eventually get re-injured. This makes the preventive exercises we discuss further below so important.

Other modifiable factors include

  • hamstring weakness, 
  • muscle fatigue,
  • decreased flexibility,
  • running speed,
  • lack of warmup  and
  • poor running technique.

Running Form patterns associated with hamstring injuries (4) are

A runner exhibiting running form risk factors for hamstring strains (heel strike, insufficient forward lean, overstriding)
Overstriding, Heel Striking and insufficient forward lean are running form related risk factors for hamstring strains.

Treatment of Hamstring Strain in Runners and Preventive Exercises

The treatment of a runner for a strained hamstring will aim to

  • address any weakness in the injured muscle, 
  • mitigate any reduced muscle flexibility due to scar tissue from the injury
  • adapt running form that might have contributed to the injury.

Treatment can be divided into 3 phases. These phases and corresponding exercises described below are – with some adjustments – primarily taken from an excellent paper (5) by Heiderscheit et al, in the Journal of Orthopaedic & Sports Physical Therapy.

Initial Recovery Phase (Phase I)

The initial phase of recovery focuses on managing pain, protect healing tissue, minimize muscle and strength loss and to prevent motion loss.

Keep moving but avoid any movement that causes pain, which indicates excessive stretching of the hamstring. To achieve this you might have to walk with shorter strides than usual. Do not run during this phase.

Ice the injured area 2-3 times per day to reduce inflammation and pain. If swelling is severe consider applying compression with an (elasticated tubular) bandage to the thigh to limit further swelling.

Recovery exercises in phase I are designed to promote neuromuscular control, while avoiding excessive motion and muscle damage. These exercises should be performed daily and be performed at a pain free intensity.

  • Stationary bike (10 min)
  • Side steps in both direction, 3×1 min 
  • Grapevines / Cariocas at relaxed pace
  • Fast feet drill (2×1 min)
  • Plank (5x 10 sec)
  • Side plank (5x 10 sec on both sides)
  • Glute bridge (10 x 5 sec)
  • Balancing on a single leg, progression from eyes open to closed (4x 20 sec)

You can proceed to recovery phase II once you can walk normally and do a very slow jog without pain. You should also be able to contract your hamstrings isometrically at 50-70% of when flexing your knee to 90 degrees while lying on your belly.

Recovery Phase II

The goal of recovery phase II is to start gaining hamstring strength again and to enhance neuromuscular control of the trunk and pelvis.

Any movement in this phase should not lead to the very end of range of motion to avoid re-injury. Also avoid taking pain medication in this phase so you can listen to your body’s pain signals and stop any movement causing pain.

Continue with icing after your daily exercise to reduce inflammation and perform these exercises daily:

  • Stationary bike (10 min)
  • Side shuffle in both directions, 3×1 min , moderate to high intensity
  • Grapevines / Cariocas at moderate to high intensity
  • Boxer shuffle (2x 1 min), low to moderate intensity
  • Rotating plank, 5-s hold each side, 2×10 reps
  • Supine bent knee bridge with walk-outs (3×10 reps)
  • Single-leg balance windmill touches (4×8 reps per arm and leg)
  • Lunge walk with trunk rotation, opposite hand-teo touch and T-lift (2×10 steps per leg)
  • Single-leg dead lift (5x 10 sec, both sides)

Progress to phase III once you can jog forward and backward at moderate intensity pain-free and contract your hamstring at full strength (isometrically – i.e. without moving your leg) when flexing your knee to 90 degrees while lying on your belly.

Recovery Phase III

This is the final phase before returning to your normal training and racing regimen. Phase III focuses therefore on agility and running specific skills, while still avoiding sprinting and strong accelerations.

The goal of Phase 3 is to prepare for the return to running by being pain-free during all activities and throughout the full range of motion. The agility drill also improve neuromuscular and postural control.

Perform these exercises daily:

  • Stationary bike (10 min)
  • Side shuffle in both directions, 3×1 min , moderate to high intensity
  • Grapevines / Cariocas (3x 1 min) at moderate to high intensity
  • A skips and B skips with progressively increasing knee height.
  • Forward-backward accelerations (3 × 1 min); start at 5 m, progress to 10 m, then 2 m 
  • Rotating plank with dumbbells, 5-s hold each side, 2×10 reps
  • Supine single-limb chair-bridge, 3 × 15 reps, slow to fast speed 
  • Single-leg balance windmill touches with dumbbells (4×8 reps per arm and leg)
  • Lunge walk with trunk rotation, opposite hand-teo touch and T-lift (2×10 steps per leg)

You are ready to return to your running if you

  • If you are able to repeat 4 consecutive maximum strength efforts while lying on your belly and flexing your knee at 15° (extended) and 90° (flexed)
  • Can operate across the full range of motion without pain
  • Can run at near maximal speed without pain (slowly increase your pace towards maximum over the course of a few intervals to test this out).

Other injuries that may be confused with hamstring strains

Hamstring strains are different from hamstring tendinopathy. Hamstring tendinopathy  is caused by inflammation of the tendon that attaches the hamstring to your sitting bone. It typically causes  pain from the buttocks down the leg and gets worse with periods of sitting, walking or running.

In hamstring tendon avulsions the hamstring tendon completely separates from the bone. Sometimes when this happens a part of the bone stays with the tendon. In ischial apophyseal avulsions a piece of the sitting bone has stuck to the hamstring tendon as it broke off.

Referred pain from other parts of the body that is felt at the back of your thigh could be another source of pain similar to hamstring strains. Such “referred” pain could originate from a prolapsed disc, strained muscles in the lower back. 

If you are unsure about the true source of your hamstring pain, then a visit to a healthcare professional will clear up any doubt. (6)

A medical professional pondering the question - Hamstring strain... or not?

Do the work to stay free from hamstring strains

If you are a runner and suffering from hamstring strain right now the great news is that you are nearly guaranteed to see your injury go away by following the 3-phase recovery protocol described above. 

The trick is to stay injury free and avoid the high risk of re-injury. For this make sure to follow all phases of the recovery plan before you return to sport. Then make it a habit to build some of the exercises introduced into your regular strength workout program. (You have one, right?).

Also make sure that none of the running form flaws associated with hamstring strains in runners (Heel striking, Insufficient forward lean, Overstriding) is part of your personal running form. An easy way to check this is our online, AI enabled running form evaluation at Movaia.com, or talk to your running coach or physiotherapist.

With this you should be set on a path to injury free running – happy running!

References and further reading on hamstring strain in runners

  1. Danielsson, A., Horvath, A., Senorski, C. et al. The mechanism of hamstring injuries – a systematic review. BMC Musculoskelet Disord 21, 641 (2020). https://doi.org/10.1186/s12891-020-03658-8
  2. Clanton, Thomas O. MD; Coupe, Kevin J. MD. Hamstring Strains in Athletes: Diagnosis and Treatment. Journal of the American Academy of Orthopaedic Surgeons 6(4):p 237-248, July 1998. 
  3. Subbu R, Benjamin-Laing H, Haddad F. Timing of Surgery for Complete Proximal Hamstring Avulsion Injuries: Successful Clinical Outcomes at 6 Weeks, 6 Months, and After 6 Months of Injury. The American Journal of Sports Medicine. 2015;43(2):385-391. doi:10.1177/0363546514557938
  4. Sugimoto, D.; Kelly, B.D.; Mandel, D.L.; d’Hemecourt, D.A.; Carpenito, S.C.; d’Hemecourt, C.A.; d’Hemecourt, P.A. Running Propensities of Athletes with Hamstring Injuries. Sports 2019, 7, 210. https://doi.org/10.3390/sports7090210
  5. Heiderscheit BC, Sherry MA, Silder A, Chumanov ES, Thelen DG. Hamstring strain injuries: recommendations for diagnosis, rehabilitation, and injury prevention. J Orthop Sports Phys Ther. 2010 Feb;40(2):67-81. doi: 10.2519/jospt.2010.3047. PMID: 20118524; PMCID: PMC2867336.
  6. Lauren N. Erickson, Marc A. Sherry, Rehabilitation and return to sport after hamstring strain injury, Journal of Sport and Health Science, Volume 6, Issue 3, 2017, Pages 262-270, ISSN 2095-2546,  https://doi.org/10.1016/j.jshs.2017.04.001.