running shoes and injury
A new study on "The Effect of Running Shoes on Lower Extremity Joint Torques" (text, PDF) notes that "Increased joint torques at the hip, knee, and ankle were observed with running shoes compared with running barefoot:"
Disproportionately large increases were observed in the hip internal rotation torque and in the knee flexion and knee varus torques. An average 54% increase in the hip internal rotation torque, a 36% increase in knee flexion torque, and a 38% increase in knee varus torque were measured when running in running shoes compared with barefoot.
A 6% increase in stride length was observed in the shoe-wearing study participants, commonly associated with a more pronounced heel strike--which is enabled by cushioned shoes. The study's conclusion looks to minimalist shoes as a goal:
The development of new footwear designs that encourage or mimic the natural compliance that normal foot function provides while minimizing knee and hip joint torques is warranted. Reducing joint torques with footwear completely to that of barefoot running, while providing meaningful footwear functions, especially compliance, should be the goal of new footwear designs.
(h/t: Runner's World Peak Performance and BarefootRunningShoes.org)