Hamstring Strains: What Are They?
Hamstring strains are extremely common in the athletic performance population especially during running events.
- They can occur with longer distance running where change of pace can fluctuate throughout the run or at a steady pace when the time under tension exerted on the tissue exceeds the tissue’s ability to withstand the demands of the activity.
- Hamstring strains also can occur during longer runs with change in elevation and terrain that requires fluctuating demands of acceleration and deceleration.
- Another common time for hamstring strains to occur is during sprinting when the tissue cannot withstand the demands of the movement mechanics and forces.
Why Are Hamstring Strains Common?
The reason why hamstring strains are very common and the typical “pulled a hammy” when running fast occurs is because these muscles attach across two joints.
They originate on the ischial tuberosity, otherwise known as your “butt bone” and insert across the knee at the tibia and fibula.
Anatomy of the hamstring musculature, demonstrating origin and insertion to appreciate the multipoint function.
What Muscles Make Up The Hamstring?
The hamstrings comprise of 3 major muscles:
- Semimembranosus
- Semitendinosus
- Biceps femoris
The first two reside on the inside of the back of the thigh while the short and long head of the bicep femoris is located on the outside of the thigh.
What do the semimembranosus and semitendinosus do?
The semimembranosus and semitendinosus flex the leg at the knee and when the knee is bent, rotate the tibia medially.
What does the biceps femoris do?
The biceps femoris flexes the knee and rotates the tibia laterally.
All the muscles help to extend the hip and trunk.
What else do the hamstrings do?
- The hamstrings also work to control the rate of acceleration of the leg when moving forward.
- They also act to decelerate the leg by not only eccentrically contracting but also through isometric forces.
Eccentric Hamstring Contractions
Eccentric means that as the hamstring lengthens, so as the leg moves forward, the tissue is also contracting to control how fast the leg moves forward.
Picture a rubber band being pulled and the hamstrings basically control the rate of how fast the rubber band stretches.
Isometric Hamstring Contractions
Hamstrings also work isometrically as they will contract and hold the position of the leg against force.
Deficiency in isolated hamstring eccentric and isometric strength has been contributed to strains or tears.
- Poor motor control of the hamstrings results in the inability to stabilize the pelvis, hip and knee during dynamic movement, contributing towards injury.
- Over powering hip flexors, poor pelvic positioning, lumbar compensation and improper loading are also factors seen with injury to the hamstrings.
The Different Types Of Hamstring Strains
A strain is an over stretching of the muscle tissue where tearing of the muscle fibers occurs due to the inability to control against the forces being acted upon it.
A grade 1 strain is a minimal amount of tissue where a grade 3 is a massive amount of tissue.
Severe injury can result in an avulsion tear where the tendon that attaches the hamstrings to the ischial tuberosity, pulls off of the bone.
Avulsions are very rare at the insertion point at the knee as most of the forces occurring are distally at the knee and being resisted higher up in the muscle tissue.
Generally, individuals are stronger in their hamstrings distally more than proximally.
How To Rehab From A Hamstring Strain
Strains are painful and the progression back into exercise needs to be modified and controlled.
This IS NOT the type of pain to push through.
The pain is a message that the tissue cannot tolerate the loads being applied at the time.
Working through high pain movements and positions is not a proper learning environment for the neuromuscular system and often compensation will occur to avoid the pain.
A recent study just compared pain threshold vs. non-painful exercise in rehabilitation of hamstring strains.
- In both groups, pain threshold with controlled exercises at a 4/10 pain and the no pain exercise group demonstrated improvement in isometric and eccentric strength.
- Neither group demonstrated a difference in the time of return to play function but tissue integrity improvements were found, indicating that healing and mother nature need to take place but while healing is occurring, engaging in proper exercises, with proper load and pain levels can help for a smoother and appropriate recovery.
- Improper engagement in exercise and pain levels with these types of strains can produce further damage and prolong recovery.
The Best Rehab Exercises For Hamstring Injuries
The following are some basic exercises that can be done as preventative of injury to the hamstrings as well as rehabilitating after a strain.
As always, severe injury, resulting in pain or dysfunction without progress, should always be evaluated by a medical professional.
Exercise #1: Active Straight Leg Raise Supine/Reactive Neuromuscular Training
Limited active straight leg raise.
The ability to perform an active straight leg raise to 85-90 degrees perpendicular to the ground is important as it demonstrates good mobility of the posterior chain and hip.
To correct a deficient active straight leg raise there is a technique used to help the neuromuscular systems learn to reduce the tension in the tissue and improve the leg raise.
Start position of the active straight leg raise neuromuscular retraining technique and end position demonstrated with control of the pelvis and positioning of the legs.
- Start by lying on your back with an elastic band around one foot. Pull the band to raise the leg up to as far as you can go while keeping it straight.
- Ensure your pelvis is level and rotated back without arching of the low back.
- While maintaining the pelvic position, raise the opposite leg equal to the other leg. Then lower down while keeping the banded leg up.
The goal is to allow the one leg to stretch while controlling your core and executing a repeated leg raise on the other side.
You are retraining your neuromuscular programming for proper control and function of the pelvis and hamstrings.
Repeat 10 times on each leg or continue until you see improvement in your active straight leg raise.
Exercise #2: Toe Touch Progression
The ability to touch the toes demonstrates full mobility of the posterior chain and lumbar spine in a functional position. Lifting items from the floor requires this movement to be functional to avoid compensation.
The inability to reach the toes is generally due to tension in the hamstrings.
The toe touch progression retrains the neuromuscular system to reduce tension in the hamstrings while using core control to flex forward and stand tall.
The foam roll helps to apply more stretch to the posterior chain as well as challenge the center of gravity for balance for neuromuscular control throughout the range.
- Start by standing with your toes up on a half foam roll or an item that raises the toes a few inches off the ground while keeping the heels on the ground.
- Put a ball or yoga block between your knees.
- While squeezing the object, go down to touch your toes. You can bend the knees to get there.
- Squeeze the object the entire time down and all the way up tall.
- Repeat 10 times and then repeat with the heels raised up and toes on the floor.
Exercise #3: Hamstring Foam Rolling
With the foam roller under the thigh, assume the position as shown above.
- Roll the leg down to just above the back of the knee and up to the butt bone.
- You can rotate the leg inward and outward to address medial and lateral portions.
- Avoid pain over 3/10 by unloading your bodyweight through your other leg and arms.
- Repeat 25-30 rolls.
Exercise #4: Supine Hamstring Isometric Hold
Hamstring supine isometric. Controlling the pelvis while pulling the heel into the ground.
Assume the hook lying position as shown.
- Ensure the pelvis is level.
- Dig your one heel into the ground to produce tension in the muscle with no greater than a 3/10 pain.
- Focus on digging your heel into the ground and pulling.
- Hold the tension for 5-8 seconds. Repeat 10 times.
Exercise #5: Prone Hamstring Isometric Hold
Lying on your stomach, loop both heels into a band.
- Start with the knees bent at 90 degrees.
- Lower one leg while allowing the other leg to hold the resistance of the band.
- Ensure the pelvis stays in contact with the floor and avoid arching the low back.
- Hold for 5 seconds; repeat 10 times on each leg.
Exercise #6: Eccentric Single Leg Bridge
Start by lying on your back with your feet propped up onto a stool or small box.
- Rotate the pelvis back and ensure it is in neutral position while avoiding arching the back.
- While maintaining that position, raise your hips up.
- At the top position, raise one foot off of the stool while maintaining pelvic stability and slowly lower your hips back down to the ground through the one leg.
- Repeat 15 times on each leg.
Exercise #7: Straight Leg Bridge
Lying on your back with a foam roll under the back of the knee, pull one leg up to your chest as shown above.
- Ensure the pelvis is neutral and avoid arching the back.
- Keep the leg on the foam roll straight and avoid rotating the leg outward. This will prevent medial stress to the knee.
- Raise your body upwards through the one leg on the foam roll. Lower down with good control.
- Start with the under the knee position. As it gets easier, progress to the under the ankle position.
- Repeat 15 times each leg.
Exercise #8: Eccentric Hamstring Sliders
If you have furniture sliders or VAL sliders, start by lying on your back with your feet on the sliders.
- Assume the neutral pelvis position and raise yourself up into the bridge position.
- Staying at the top position, maintain the pelvic position and slowly straighten your legs outward until fully straight.
- Drop down and then pull the sliders back to the start position and repeat 15 times.
Exercise #9 & #10: Hip Hinge and Reverse Dead lift
Using a pole or dowel, position it behind your back with contact points being the back of your head, between your shoulder blades and tailbone.
- While maintaining all three points of contact, push your butt outwards behind you while bending the knees.
- Make sure the knees stay over the top of the ankles and don’t translate over the toes.
- Your back should remain straight and your hips should flex at 90 degrees.
- Repeat 15 times.
Once you have the hip hinge movement down, add resistance.
- Holding a kettle bell, dumbbell or a light barbell weight, start in the top position.
- Keep the should blades squeezed back, head neutral and begin to slowly lower the weight down in the same manner as the hip hinge exercise.
- Lowering down slowly at a 5 second count will ensure proper form and eccentric loading of the posterior chain.
- Repeat 10-15 times.
There are some more advanced posterior chain and hamstring loading exercises out there, specifically the Nordic hamstring curl, gluteal/hamstring drop in the GHD machine and single leg loading movements.
The exercises described here are good options to help stimulate the tissue in a controlled manner to promote healing and restore function.
Often these movements are deficient in many individuals and these basics need to be practiced before progressing to more advanced exercises. These are a good place to start when experiencing a hamstring injury or if you want to work the basics for hamstring function.
As improvement is seen and the positions are functional and non-painful, progression to more advanced exercises is then appropriate.
About The Author:
Michael St. George PT, DPT has been practicing for 10 years primarily in the outpatient and orthopedic setting. He works for a physical therapist owned private practice based in the greater Philadelphia area and surrounding suburbs. Mike is certified through Functional Movement Systems for FMS, SFMA and FCS which consist of screens and testing used to measure movement quality and performance. Mike also has experience with working with numerous surgeons and physicians from the Rothman institute. Currently he works primarily with ACL, meniscus and post surgical recovery and sports injuries, return to sport testing and performance, running evaluation and re training and hand and upper extremity conditions.
References:
Hickey, J., Timmins, R., Maniar, N., et al. (2020) Pain-Free Versus Pain Threshold Rehabilitation Following Acute Hamstring Strain Injury: A Randomized Controlled Trial. Journal of Orthopaedic & Sports Physical Therapy. Vol 50 (2) 91-103
