One of the many proven upsides to forefoot running is healthier knees, including a more safeguarded ACL, a major ligament in the knee that helps stabilize the joint.
Unlike heel strike running, one of the ways forefoot running is more protective on the ACL is by making the ankle better at reducing impact and improving stability on the lower leg, including the knee. A study in the Journal of Athletic Training found that forefoot running increased the range of motion of the dorsiflexors (small muscles that line the top of the foot and extends to the ankle) which reduced ACL loading by stabilizing the knee and hip joints.
A similar study in the Journal of Sports Science and Medicine drilled this point home as their results found that the range of motion of the knee and ankle joints increases and decreases depending on foot strike pattern, and more specifically, the ankle functions dramatically different in heel strike running than in forefoot strike running.
The study found that heel strike running caused unstable motions in the knee-joint which directly increased mechanical work and stress on the ACL, which is why ACL injuries will always be more likely in heel strike runners, not in forefoot runners. But, what’s worse, the study found heel strike running prevented the ankle from aiding in foot-step stability and impact absorption, projecting more mechanical demands and impacts on not just the knees, but the hips, rendering even more areas vulnerable to injury.
The Take Home Message
There’s always going to be more stress on the ACL in heel strike running because the mechanical configuration of the ankle joint causes the knee to bear the brunt of any excessive impact, which is also why the number of running-injuries continues to move upwards in heel strike runners over forefoot runners.
This is why people really need to be more aware of the undeniable fact that foot strike type directly alters your collective mechanics which directly affects the amount of physical stressors on your body. Never lose sight that forefoot running produces more functional engagements of the ankle, making it better at stabilizing the knee, while protecting the knee from impact. To this point, here are all the other injuries of heel strike running that forefoot running perfectly prevents!
References:
Fong, C.M., Blackburn, J.T., Norcross, M.F., Mcgrath, M. and Padua, D.A. (2011) Ankle-dorsiflexion range of motion and landing biomechanics. Journal of Athletic Training 46, 5-10.
Valenzuela et al. Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics. J Sports Sci Med, 2015, 14, 225-232
Bretta Riches
BSc Neurobiology; MSc Biomechanics candidate, ultra minimalist runner & founder of RunForefoot. I was a heel striker, always injured. I was inspired by the great Tirunesh Dibaba to try forefoot running. Now, I'm injury free. This is why I launched Run Forefoot, to advocate the health & performance benefits of forefoot running and to raise awareness on the dangers of heel striking, because the world needs to know.