Hamstring injuries are still all too common in athletics, however, the scientific community is discovering more about the inner workings of the several mechanisms responsible for causing these painful injuries. Today you will witness a series of potential causes for hamstring strains along with simple remedies to prevent the likelihood of one occurring to you or an individual with whom you work with. First, let us examine the hamstring anatomy very briefly, so you know exactly what you are working with. You’ll then appreciate just how intricate this muscle group is when it comes to athletic movement.
FUNCTIONAL HAMSTRING ANATOMY
The Hamstring Complex consists of 4 primary muscles that are for the most part bi-articular. Meaning they cross and operate at both the knee and hip. The hamstring originates at or near the Ischial Tuberosity and then inserts at various points along the tibia and fibula, respectively.
*Concentrically these muscles can extend the hip and flex the knee through acceleration, with accessory motions involving either external or internal rotation depending on the muscle in question.
Eccentrically the hamstrings decelerate both hip flexion and knee extension with either external rotation or internal rotation.
Now that you have a basic understanding of hamstring anatomy, let’s dive into some uncommon reasons why this particular group of muscles becomes injured:
Potential Hamstring Injury Causes:
#3-Anterior Core Deficiency
It’s pretty well documented and understood what the hamstring’s role is in injury prevention and function at the hip. But what isn’t so often discussed is the powerful role the hamstrings play at the knee (distally) during sprinting. Research years back showed that hamstring activity was at its highest just before and immediately after ground contact. What this means is that the hamstrings have to slow down knee extension in the swing leg, and then be able to quickly turn around and reverse motion to help propel us forward at push-off. Unfortunately, when you break this situation down, you’ll quickly realize it can be a silent issue that not many recognize. And if you aren’t training deceleration at the knee, along with straight knee hip extension work, then injury becomes much more likely. Below is a short list of drills you can do to train the hamstrings to learn to decelerate the knee effectively during sprinting
Eccentric Knee Work:
*Slide board Leg Curls
*Val slide Leg Curls
Check out the “Sway-back” posture from the image above. You’ll notice just how far forward the hips are displaced. What occurs here is that your hamstrings become overly active (synergistic dominance) as the glutes fail to maintain a neutral position of the femoral head in the acetabulum. Moreover, the Psoas muscle group and hip flexors become very weak which can further overload the hamstrings over time since the hip flexors lose optimal muscle length and strength capacity. Your best bet here is to prescribe psoas progressions starting from a supine position (ie. Dead-bugs), then progressing to a prone (i.e. mountain climber variations), and eventually operating from a standing position (i.e. Marching).
Anterior Core Weakness
Just like with your deep hip flexors being weak, any core or abdominal weakness, or even overactivity of certain abdominals can lead to an overused, burned-out hamstring complex. This is why it’s so vital to lift heavy with your squat, deadlift, and single-leg progressions week and week out. This will guarantee that your deep abdominals become and remain very strong to help keep your lumbar spine stiff. As a result, you will experience improved posture and muscle balance throughout your hips and lower extremities, and your hamstrings will thank you for it.
Ankle Mobility Issues
I would like you to visualize this scenario for a moment if you will. Tilt your pelvis backward, and shift weight into your forefoot. You will instantly notice that in this position your ankle is locked and your calves are perpetually turned on. What’s one of the most common postures that everyone would agree on? Anterior pelvic tilt should have been your answer! This posture is a direct reflection of what happens in your distant lower body when your calves are tight. Just like the examples above, increased anterior pelvic tilt, knee hyperextension, and calf tightness cause restrictions in the ankle that will inevitably overload your hamstrings. Credit to world-renowned track and field coach Boo Schexnayder for bringing this injury factor to light years ago.