Hamstring Strain
Why care?
If you haven’t had one yourself, chances are you have a teammate who has; “pulling a hammy”, medically known as a hamstring (biceps femoris) strain is hands down one of the most common injuries experienced in soccer. In 2012 it was estimated that hamstring strain was the most prevalent injury in European Soccer, consisting of 12-17% of all injuries and resulting in an average of 15 missed matches per team (Liu et al, 2012).
How & Why:
Typically, these occur when someone goes to “kick it in gear” when already running or sprinting, or making a quick break for the ball. There are two points during the same stride that the strain may happen. The first is during the eccentric hamstring contraction phase when the leg is swinging and reaching out in front, yet prior to contact with the ground. The second is almost instantaneous with the moment that striding foot makes contact with the ground, because the huge increase in demand. Upon contact with the ground, the hamstrings are suddenly not responsible for accelerating the weight/inertia of the leg relative to the body but, rather, accelerating your whole body while supporting your weight.
Prevent it:
The most supported risk factors for hamstring strain are the following: A) muscle imbalance between concentric quadriceps strength and eccentric hamstring strength; B) number of previous hamstring injuries; C) hamstring flexibility deficit (unable to fully straighten knee): and D) hamstring pain or discomfort with manual pressure to muscle shortly after returning (being cleared) to play after an injury-induced absence.
Due to the huge kinematic range of motion that the hamstrings must function across during running, flexibility is very important. The more flexible you are, the farther from available ‘end-range’ your hamstrings are during the moment in running when they are required to work in a stretched position, thus decreasing their risk of being strained.
Eccentric conditioning of the hamstrings are equally important, because this is the type of work demanded of them during this high-stress moment and, as stated above, this is by far the #1 most influential factor for predicting your risk of injury when strenght is compared to your quadriceps. As such, preparing for this kind of functional eccentric hamstring work and training the muscles accordingly is critical. So, for exercises: Eccentric straight leg deadlifts, nordic hamstring ‘fall outs’, and eccentric (alternating) hamstring ball rollouts.
You already know hamstring stretches, so I won’t bore you with them. Still, keep in mind that with stretching, it’s not a ‘no pain no gain’ situation. Yes, you should feel it stretching, but you don’t need to kill yourself doing it. You are better off holding a light stretch for 2-3 minutes, 3 times per day than swearing and cursing with searing stretching pain for 10-15 seconds, bouncing into the stretch, 2 times per day. Yes, really. Research shows that it’s not how long you hold a stretch for in a single bout - it’s the total time as it adds up. You want at least 2-3 minutes of total time under stretch. You can hold a stretch for 6 x 30 seconds, or 3 x 60 seconds: Similar, if not exactly the same effect.
For tips of getting a better, more sustainable stretch (and for a recap of this article), see the video above.