What is a Hamstring Strain?
A hamstring strain is a common leg injury involving a tear in one or more of the hamstring muscles. A hamstring strain can range from mild to very severe involving a complete tear of the hamstring muscle.
You have four hamstring muscles: semimembranosus and semitendinosus (medially) and biceps femoris - short and long heads (laterally).
What Causes a Hamstring Strain?
Common reasons for hamstring strain or injury can be categorized as primary or secondary.
Poor timing-inter-muscular coordination and eccentric strength in the hamstring muscles during the switch between late leg recovery and initial leg approach in the swing phase of sprinting.
Lack of “stiffness” and eccentric strength in the hamstring muscles during the ground contact phase of running. “Stiffness” refers to the ability of the hamstring muscle to absorb shock and rebound. Dropping a golf ball onto concrete is an example of stiffness, it immediately rebounds off the surface. This stiffness is what gives sprinters the oomph they need to take off and slow down. As a professional athlete at one point, it was actually recommended to me to NOT over stretch because it would take away from my speed and agility.
Previous hamstring strain is a very good indicator of potential for future injury.
Poor running mechanics. This consists primarily of overstriding or poor pelvic control, which puts the hamstrings in a vulnerable position at ground contact.
Improper warm-up. Your warm-up must be active and dynamic to prepare the hamstring muscles for the forces involved. Passive stretching is only one segment of warm-up.
Inappropriate training loads. Your hamstrings are primarily fast twitch Type II fibers that fatigue quickly. High-speed work should be done early in the workout, as close to warm-up as possible to avoid fatigue.
Lower back pathology. Abnormalities of the lumbar spine or poor pelvic control that can cause nerve dysfunction and subsequent muscle weakness can predispose you to injury.
Playing surfaces. A wet slippery surface will put more strain on the hamstring due to slipping.
What are the Symptoms of a Hamstring Strain?
Mild hamstring strains may feel more like a tightness or low-grade ache in your hamstring. Severe hamstring strains can be extremely painful, making it impossible to walk or even stand.
Other possible symptoms of a hamstring strain are:
Sudden and severe pain during exercise
along with a snapping or popping feeling
Pain in the back of the thigh and lower buttock when walking, straightening the leg, or bending over
How is a Hamstring Strain Diagnosed?
Pulled hamstrings are graded 1, 2 or 3 depending on severity.
Ultrasound scan and MRI are able to identify the location and extent of your hamstring tear.
Grade 1 Hamstring Strain
With a grade 1 hamstring strain, you may have tightness in the back of the thigh but will be able to walk normally. You will be aware of some hamstring discomfort and unable to run at full speed. There will be mild swelling and spasm. Bend your knee against resistance is unlikely to reproduce much pain.
Grade 2 Hamstring Strain
With a grade 2 hamstring strain, your walking pattern will be affected and you will most likely be limping. Sudden twinges of hamstring pain during activity will be present. You may notice some hamstring muscle swelling and your hamstring will be tender to palpate. It will also be painful for you to bend your knee against resistance.
Grade 3 Hamstring Strain
A grade 3 hamstring strain is a severe injury involving a tear to half or all of the hamstring muscle. You may need crutches to walk and will feel severe pain and weakness in the muscle. Swelling will be noticed immediately and bruising will usually appear within 24 hours.
Diagnostic MRI may also be used to specifically identify the grade of hamstring tear and its exact location.
Beware of Referred Hamstring Pain!
Due to your sciatic nerve passing through the hamstring muscle group, a lower back injury or some other injury that pinches the sciatic nerve can replicate the symptoms. It is vital that you seek a professional diagnosis from an expert in hamstring and back injuries.
Hamstring Strain Treatment
Many people with a hamstring start to feel better within a few days of the injury. However, there is an extremely high hamstring re-injury rate due to a poor rehabilitation process.
Hamstring strains are one injury that professional guidance is highly recommended for both an accurate diagnosis but also provide you with the best chance of avoiding repeat hamstring injuries.
Repeat hamstring injuries have unfortunately curtailed many a bidding athlete’s career.
Your rehab program will aim to:
Reduce hamstring pain and inflammation.
Normalize your muscle range of motion and extensibility.
Strengthen your knee muscles and hamstrings.
Strengthen your lower limb muscles: calves, hip and pelvis muscles.
Normalize lumbo-pelvic control and stability - a co-factor in many hamstring strains.
Normalize your neurodynamics to enable your sciatic nerve to pass freely without scar adhesions.
Improve your game speed
agility and balance
Improve your technique and function eg running, sprinting, jumping, hopping and landing.
Minimize your chance of hamstring re-injury.