Many elite distance runners run with a forefoot strike and rarely suffer major injuries, such as a broken femur –this is because forefoot runners demonstrate a significantly lower impulse wave at touchdown as compared with heel strike running [1].
Recently however, elite distance runner, Krista Duchene –who is a heel striker– broke her femur towards the end of a half-marathon, but with incredible determination to finish, she did just that, achieving third place. Thankfully, Duchene’s femur was repaired with a plate and three screws.
Could Duchene’s heel strike running style be the most important reason for her injury?
Historically, femur fractures are rare in elite distance running —think about it. When was the last time you heard of an elite runner breaking their femur?
In my opinion, the nature of Duchene’s injury is concerning because it may have been caused by her pronounced heel strike landing.
- The impulse wave that is generated at heel strike is the result of abrupt braking of the foot with the ground whereby the magnitude of the heel strike-impulse wave is implicated in the development of stress fractures [1-3].
What is more, fatigue that accompanies the end of a long distance run, reduces the shock attenuation capacity of the soft tissues, bones and articular joint cartilages, thereby amplifying the impact pulse at each heel striking step.
Shoes Increase Impulse Wave During Heel Strike Running
Rather than modifying landing behavior to reduce bone loading, solutions traditionally employed by most coaches include thicker cushioned footwear. However, the leading theory holds that such shoes actually exaggerate the interaction of force variables affecting foot-ground contact during running, meaning that increased shoe cushioning results in greater landing forces with which the foot hits the ground [4,5]. Therefore, Duchene’s heel strike running form coupled with inadequate footwear accounted for the potentially high repetitive loading which most likely resulted in a stress reaction and then fracture to the femur.
Why Most Elite Runners Avoid Heel Strike Running
Most elite runners prefer a forefoot strike landing because of its unmatched ability to reduce shock and allows the lower leg to store a considerable amount of potential energy in a minimal interaction with the ground [6].
It is quite possible that Duchene’s disastrous scenario could have been prevented had she been a forefoot striker. By comparison, Warden et al. 2014 found that structural fatigue in the leg bones can be prevented by instructing the runner to land softer with a higher step rate, which are components of forefoot running.
The Take Home Message
Whether inadequate training tactics, diet, or something else contribute to a femur fracture, heel striking was probably closely linked to Duchene’s injury because at some point, the relative contributions of these high impact landings may have been the greatest stressor on her femur over-time.
More From Run Forefoot:
Tips on How to Run Forefoot More Efficiently
Thick Heeled Running Shoes Cause Unnatural Gait
Forefoot Running Eliminates Shin Splints
Best Shoes for Forefoot Striking
References:
[1]. Daoud et al., Foot strike and injury rates in endurance runners: a retrospective study. Med Sci Sports Exerc, 2012; 44(7):1325-34.
[2]. Sasimontonkul, S., Bay, BK and Pavol, MJ. Bone contract forces on the distal tibia during the stance of running. J Biomech, 2007:40(15):3503-9.
[3]. Warden et al. Management and prevention of bone stress injuries in long-distance runners. J Orthoped Sports Phys Ther, 2014; 44(10):749-817.
[4]. Nigg, BM and Morlock, M. The influence of lateral heel flare of running shoes on pronation and impact forces. Med Sci Sports Exerc, 1987; 19(3):294-302.
[5]. Kersting, UG., Kriwet, A and Bruggemann, GP. The role of footwear-independent variations in rearfoot movement on impact attenuation in heel-toe running. Res Sports Med, 2006; 14(3):117-34.
[6]. Sellers et al., Evolutionary Robotic Approaches in Primate Gait Analysis. Intern Journ Primate, 2010; 31(2):321-338.
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.
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