Hamstrings stretch exercise

Exercises that mimic special tests series.

This series highlights some exercises that mimic positions of special tests. Recognizing this crossover between the interventions we use and the research-supported symptom patterns evoked can help us guide intervention, exercise modification, and diagnosis.

Hamstrings stretch with strap: with the knee extended, use a stretch-out strap to lift the leg off the table until a pull is felt in the posterior leg

Straight leg raise: with the PT holding the knee in extension, the PT raises the leg from the table, instructing the patient to notify the PT when radicular symptoms or back pain are reproduced. The test aims to bring the sciatic nerve into a position of increasing tension to evaluate the impact of neural tension on patient symptoms. The angle that the leg is lifted is then measured. This test can be modified to bias certain peripheral nerves.

The similarity in position between these two tests reinforces the need to monitor symptoms when prescribing a new exercise. Symptoms distal to the knee or symptoms in the low back indicate a need to modify or discontinue this exercise. Patients may need additional education about the inelasticity of nerves-- I've often had patients insist they need a certain stretch because they feel a "pull." By educating these patients on the location of a target muscle vs nerve we can help our patients interpret their symptoms more accurately and discontinue nerve "stretches"-- perhaps in favor of nerve glides!

Although tested in standing, the Puranen-Orava test for chronic proximal HS tendinopathy places the joints in a similar position to commonly used hamstring stretches, so is worth reviewing to ensure appropriate symptom interpretation. A positive test here is pain in the proximal hamstrings tendon when standing with 90 degrees hip flexion and full knee extension. To further confirm this diagnosis, Cacchio et. al developed a cluster of tests that will provoke similar symptoms if hamstring tendinopathy is the prevailing diagnosis. Overall, it is clear from the above tests that symptom location is once again key to symptom interpretation.

After writing this article, I was excited/surprised to see that one of my PT school professors just published in the European Journal of Physical Medicine and Rehabilitation closely related to this topic! Her 100 participant study observed how a 60 second hamstrings stretch decreased dermatomal somatosensory evoked potentials-- and that these changes persisted for 24 hours! Inclusion criteria for the study included older adults with hamstrings tightness, so I would be interested to see if 30 sec is still appropriate for patients with known sciatic neuropathy.

Many common hamstrings stretches used in the athletic population can similarly alter sciatic tension (see a couple more examples below). In the clinic I like to favor HS stretches that maintain a neutral spine and increase the angle of hip flexion while allowing a softly bent knee, such as a 1/2 kneeling or supine active popliteal angle position. These positions tend to get better symptom distribution subjective reports by my patients; however, I would love to see more research come out about the pros and cons of different hamstrings stretches.

Mary Kate Halligan, PT, DPT

Moustafa, IM, Ahbouch, A, Palakkottuparambil, F, Walton, LM. Optimal duration of stretching of the hamstring muscle group in older adults: a randomized controlled trial. European Journal of Physical and Rehabilitation Medicine. 2021.