I am at the airport at the moment and this new study just turned up. I thought it was worth putting up without writing much as I don’t have that much time. I am going to be travelling for the next 36 hrs, so may not get back to finish writing about this research for a few days, but the information in the abstract speaks for itself:
Joint contact loading in forefoot and rearfoot strike patterns during running.
Rooney BD, Derrick TR.
J Biomech. 2013 Jul 30.
Research concerning forefoot strike pattern (FFS) versus rearfoot strike pattern (RFS) running has focused on the ground reaction force even though internal joint contact forces are a more direct measure of the loads responsible for injury. The main purpose of this study was to determine the internal loading of the joints for each strike pattern. A secondary purpose was to determine if converted FFS and RFS runners can adequately represent habitual runners with regards to the internal joint loading. Using inverse dynamics to calculate the net joint moments and reaction forces and optimization techniques to estimate muscle forces, we determined the axial compressive loading at the ankle, knee, and hip. Subjects consisted of 15 habitual FFS and 15 habitual RFS competitive runners. Each subject ran at a preferred running velocity with their habitual strike pattern and then converted to the opposite strike pattern. Plantar flexor muscle forces and net ankle joint moments were greater in the FFS running compared to the RFS running during the first half of the stance phase. The average contact forces during this period increased by 41.7% at the ankle and 14.4% at the knee joint during FFS running. Peak ankle joint contact force was 1.5 body weights greater during FFS running (p<0.05). There was no evidence to support a difference between habitual and converted running for joint contact forces. The increased loading at the ankle joint for FFS is an area of concern for individuals considering altering their foot strike pattern.
Yet another study that shows where the loads go up when forefoot striking. As I keep saying: you can’t decrease the load in one tissue by changing the running form or technique without increasing it in another. Here is another recent study I previously wrote about on the same topic.
As always, I go where the evidence takes me until convinced otherwise and this just confirms that different running techniques load different tissues differently. Its six of one, half a dozen of the other.
Rooney BD, & Derrick TR (2013). Joint contact loading in forefoot and rearfoot strike patterns during running. Journal of biomechanics PMID: 23910541