Different running styles put stress on different joints in different ways. Medical professionals would like to understand exactly how different running styles affect the knee, ankle, and hip. This knowledge could help runners and other athletes recover from injuries. It could also help prevent injuries.
Researchers know that running backwards is easier on the knee. The calf muscles absorb most of the stress. Obviously, athletes can’t start running backward to avoid knee problems! So these authors studied the way three different running styles affect the leg joints.
Twenty runners took part in the study. All of them were heel-toe runners. In a heel-toe running stride, the heel hits first. The runner then rolls the weight forward through the foot. The authors taught all the runners two new running styles. Midfoot running is much like heel-toe running, but the middle part of the foot hits the ground first. The runners learned midfoot running within 15 minutes.
It was a much different story for the third running style. The authors call it pose running. Runners took about 7.5 hours to learn pose running. Pose running involves keeping the body more upright. The shoulders, hips, and ankles stay aligned. Runners don’t push off the ground as in the other running styles. Instead, they lean forward a bit, bend the knee, and avoid pushing off the running surface. In pose running, the ball of the foot hits the ground first. Pose running was designed to have leg movements that are similar to backward running.
The authors analyzed stride, speed, and ground forces for each of the three running styles. Ankle, knee, and hip movements were also studied. Pose running was slower than the other two styles. Pose running also had shorter strides and lower forces. The joints handled the load differently in pose running. The ankles worked harder, and the knees worked less.
The authors think that the different body posture may have had a lot to do with redirecting the force in pose running. They suggest that research needs to consider body position to fully understand the way the joints work while running.