Risk Factors For a Hamstring Injury
Hamstring strain is a common recurring sports injury.
Aside from interfering with your routine, hamstring injuries can cause injuries throughout the body by changing your gait, meaning that other muscles will be compensating for the injured hamstring's action.
This often manifests as lower back pain, since muscles in this region tend to compensate for the hamstrings.
On top of weak, tight hamstrings, back pain can further interfere with your performance.
Researchers have analyzed several studies to consolidate the available scientific evidence on risk factors for hamstring injury.
Surprisingly, several likely culprits weren't found to correlate with injury, including hamstring strength, hamstring flexibility and a person's weight.
While these still may be relevant factors, two that stood out the most throughout the studies assessed were quadriceps peak torque and previous hamstring injury.
Quadriceps Peak Torque In terms of muscles, peak torque is a measurement of the maximum strength capacity of a muscle.
Researchers found that, throughout the various studies assessed, higher peak torque numbers for the quadriceps were associated with higher risk of hamstring injury.
The hamstrings and quadriceps oppose one another, meaning they perform opposite actions on the same joint.
The quadriceps extends the knee, while the hamstrings flex it.
Often, muscle imbalances are present between the hamstring and quadriceps groups with the latter being stronger; this means it may fight the action of the hamstrings by exerting a strong pull on the knee, causing the hamstring to work harder to bend the knee.
This constant overworking could lead to strain.
Muscle imbalance between the quads and hamstring could explain why hamstring muscle strength itself was not found to be a strong risk factor for injury; the key may be in the balance between this muscle group and the quadriceps rather than isolated to the hamstring.
Imbalanced hamstrings may still be strong, but weaker than the quads.
Previous Injury When we injure a muscle, the body creates compensatory patterns to limit use of the muscle, preventing pain and further injury.
However, disuse causes muscle weakening that the muscle may not fully recover from without proper rehabilitation.
The quads may continue to get stronger, creating the type of imbalance described above.
Rates of hamstring re-injury are very high; sports players who have injured a hamstring have shown to be between 2 and 6 times more likely to incur hamstring injury than those who haven't already done so.
Athletes have every reason, then, to thoroughly rehabilitate their hamstrings before returning to play.
The best way to rehabilitate this muscle group is the subject of some debate.
Recently, researchers theorized that the best approach may be lengthened eccentric training.
See http://www.
ncbi.
nlm.
nih.
gov/pmc/articles/PMC3362981/#!po=13.
6364 to learn more about this rehabilitation method.
For more on the systematic review into hamstring injury risk factors, see http://bjsm.
bmj.
com/content/47/6/351.
full.
Aside from interfering with your routine, hamstring injuries can cause injuries throughout the body by changing your gait, meaning that other muscles will be compensating for the injured hamstring's action.
This often manifests as lower back pain, since muscles in this region tend to compensate for the hamstrings.
On top of weak, tight hamstrings, back pain can further interfere with your performance.
Researchers have analyzed several studies to consolidate the available scientific evidence on risk factors for hamstring injury.
Surprisingly, several likely culprits weren't found to correlate with injury, including hamstring strength, hamstring flexibility and a person's weight.
While these still may be relevant factors, two that stood out the most throughout the studies assessed were quadriceps peak torque and previous hamstring injury.
Quadriceps Peak Torque In terms of muscles, peak torque is a measurement of the maximum strength capacity of a muscle.
Researchers found that, throughout the various studies assessed, higher peak torque numbers for the quadriceps were associated with higher risk of hamstring injury.
The hamstrings and quadriceps oppose one another, meaning they perform opposite actions on the same joint.
The quadriceps extends the knee, while the hamstrings flex it.
Often, muscle imbalances are present between the hamstring and quadriceps groups with the latter being stronger; this means it may fight the action of the hamstrings by exerting a strong pull on the knee, causing the hamstring to work harder to bend the knee.
This constant overworking could lead to strain.
Muscle imbalance between the quads and hamstring could explain why hamstring muscle strength itself was not found to be a strong risk factor for injury; the key may be in the balance between this muscle group and the quadriceps rather than isolated to the hamstring.
Imbalanced hamstrings may still be strong, but weaker than the quads.
Previous Injury When we injure a muscle, the body creates compensatory patterns to limit use of the muscle, preventing pain and further injury.
However, disuse causes muscle weakening that the muscle may not fully recover from without proper rehabilitation.
The quads may continue to get stronger, creating the type of imbalance described above.
Rates of hamstring re-injury are very high; sports players who have injured a hamstring have shown to be between 2 and 6 times more likely to incur hamstring injury than those who haven't already done so.
Athletes have every reason, then, to thoroughly rehabilitate their hamstrings before returning to play.
The best way to rehabilitate this muscle group is the subject of some debate.
Recently, researchers theorized that the best approach may be lengthened eccentric training.
See http://www.
ncbi.
nlm.
nih.
gov/pmc/articles/PMC3362981/#!po=13.
6364 to learn more about this rehabilitation method.
For more on the systematic review into hamstring injury risk factors, see http://bjsm.
bmj.
com/content/47/6/351.
full.
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