2013 Part Deux

[marathondan]

I think this is what I'm getting at:

Purpose. Knee pain and Achilles tendinopathies are the most common complaints among runners. The differences in the running mechanics may play an important role in the pathogenesis of lower limb overuse injuries. However, the effect of a runner's foot strike pattern on the ankle and especially on the knee loading is poorly understood. The purpose of this study was to examine whether runners using a forefoot strike pattern exhibit a different lower limb loading profile than runners who use rearfoot strike pattern. Methods. Nineteen female athletes with a natural forefoot strike pattern and pair-matched females with rearfoot strike pattern (n = 19) underwent 3D running analysis at 4 m/s. Joint angles and moments, patellofemoral contact forces and stresses, and Achilles tendon forces were analyzed and compared between groups. Results. Forefoot strikers demonstrated 1ower patellofemoral contact force and stress compared to heel strikers (4.3 +/- 1.2 vs. 5.1 +/- 1.1 body weight, BW; P = 0.029 and 11.1 +/- 2.9 vs. 13.0 +/- 2.8 Mpa; P = 0.04). In addition, knee frontal plane moment was lower in the forefoot strikers compared heel strikers (1.49 +/- 0.51 vs. 1.97 +/- 0.66 Nm/kg; P = 0.015). At the ankle level, forefoot strikers showed higher plantarflexor moment (3.12 +/- 0.40 vs. 2.54 +/- 0.37 Nm/kg; P = 0.001) and Achilles tendon force (6.3 +/- 0.8 vs. 5.1 +/- 1.3 BW; P = 0.002) compared to rearfoot strikers. Conclusions. To our knowledge, this is the first study to show differences in patellofemoral loading and knee frontal plane moment between forefoot and rearfoot strikers. Forefoot strikers exhibit both lower patellofemoral stress and knee frontal plane moment than rearfoot strikers which may reduce the risk of running-related knee injuries. On the other hand, parallel increase in ankle plantarflexor and Achilles tendon loading may increase risk for ankle and foot injuries.

Sources here and here.