Biomechanics are a bit of a Pandora's box in the running community. Some say they're the ticket to getting faster and building endurance. Others think runners should just stick with what's comfortable and natural.
Regardless of which camp you fall into, there are a few fundamental aspects of running biomechanics that could influence running economy and performance, and certainly relate to injury prevention. Here are three areas to focus on if you're looking to improve your biomechanics, generate more power, and get faster.
1. Back Kick
During the swing phase of the gait (when the foot is off the ground and moves from behind to in front of you), the foot acts like a pendulum. Your hip is the pivot point, and your leg and foot are "suspended" from the pivot point. When it comes to pendulums, there's one really important variable: the length between the pivot and whatever object is at the end of the pendulum. In this case, it's your foot. A shorter pendulum is faster (or in physics speak, oscillates with a smaller period). Applying this to running, from a biomechanical perspective, having a shorter leg pendulum would be most economical. How do you "shorten" the leg while running/walking? The back kick. In the picture below, you'll see how pronounced the back kick is in many elite runners (this one from the front group at this year's Twin Cities Marathon). The runner then actively brings the foot and leg forward through the gait by driving his knee. (One other thing to note: this is at mile 25!)
As the right foot comes forward, the runner aggressively drives the knee upward and forward. This is where a lot of the runner's power comes from. But, he's only able to do this because of strong hip extensor muscles (muscles that are somewhat notorious for being weak in many runners). He engages his hip extensor muscles, and with a strong knee drive, also drives backwards with his left leg (the toe off part of the gait cycle). A pronounced knee drive also sets up the runner for an effective foot strike. See the next picture, particularly looking at the right leg/foot. The knee drive helps avoid excessive dorsiflexion of his foot. Dorsiflexion is when you point your toes upwards. Too much dorsiflexion usually sets a runner up for heal striking, while a more neutral position, such as in this picture, usually means a more mid-foot strike.
Two big points on the foot strike. The first is that the runner strikes mostly at his mid-foot, which tends to generate less impact forces on the lower limb joints compared to heal striking. The second point is where the foot lands relative to the rest of the runner's body. It's almost directly under the runner's head and hips. In fact, you can basically draw a straight line from the top of the head, through the torso and hips, and finishing at the heal of the foot. Having this type of alignment, with the foot striking under the hips, enables the greatest amount of power to be generated.
By focusing on these three main factors over the past few years, I've seen some huge improvements in my own racing. For example, here's a side-by-side of what my "knee drive" looked like five years ago and what it is this year.
Take time to revisit the basics. Set a good foundation and the rest will follow.
Regardless of which camp you fall into, there are a few fundamental aspects of running biomechanics that could influence running economy and performance, and certainly relate to injury prevention. Here are three areas to focus on if you're looking to improve your biomechanics, generate more power, and get faster.
1. Back Kick
During the swing phase of the gait (when the foot is off the ground and moves from behind to in front of you), the foot acts like a pendulum. Your hip is the pivot point, and your leg and foot are "suspended" from the pivot point. When it comes to pendulums, there's one really important variable: the length between the pivot and whatever object is at the end of the pendulum. In this case, it's your foot. A shorter pendulum is faster (or in physics speak, oscillates with a smaller period). Applying this to running, from a biomechanical perspective, having a shorter leg pendulum would be most economical. How do you "shorten" the leg while running/walking? The back kick. In the picture below, you'll see how pronounced the back kick is in many elite runners (this one from the front group at this year's Twin Cities Marathon). The runner then actively brings the foot and leg forward through the gait by driving his knee. (One other thing to note: this is at mile 25!)
2. Knee Drive
As the right foot comes forward, the runner aggressively drives the knee upward and forward. This is where a lot of the runner's power comes from. But, he's only able to do this because of strong hip extensor muscles (muscles that are somewhat notorious for being weak in many runners). He engages his hip extensor muscles, and with a strong knee drive, also drives backwards with his left leg (the toe off part of the gait cycle). A pronounced knee drive also sets up the runner for an effective foot strike. See the next picture, particularly looking at the right leg/foot. The knee drive helps avoid excessive dorsiflexion of his foot. Dorsiflexion is when you point your toes upwards. Too much dorsiflexion usually sets a runner up for heal striking, while a more neutral position, such as in this picture, usually means a more mid-foot strike.
3. Foot Strike
Two big points on the foot strike. The first is that the runner strikes mostly at his mid-foot, which tends to generate less impact forces on the lower limb joints compared to heal striking. The second point is where the foot lands relative to the rest of the runner's body. It's almost directly under the runner's head and hips. In fact, you can basically draw a straight line from the top of the head, through the torso and hips, and finishing at the heal of the foot. Having this type of alignment, with the foot striking under the hips, enables the greatest amount of power to be generated.
Take time to revisit the basics. Set a good foundation and the rest will follow.
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