Ankle Dorsiflexion: Even in sprinters who land on the forefoot often heel strike, a retrograde strike if you will.
Many people think of heel strike followed by midfoot/tripod contact phase followed by ankle dorsiflexion, aka ankle rocker. Heel strike is normal in the walking gait cycle. In some runners, depending on foot type, strength, flexibilty and several other factors, heel strike may be considered normal and may be essential for normal injury free mechanics. However, in recent years we tend to see the media and research investigate a midfoot or forefoot strike pattern. If you have been here with us on TGG for a year or 2-3 you will know we are big advocates of a midfoot strike pattern for several reasons which we will not go into again in this article. (Feel free to SEARCH our blog for MIDFOOT strike articles).
However, one rarely sees anyone or any source talking about the retrograde heel contact when forefoot strike patterns are used. Here, in this video, you can see several of these top level athletes who are trying to go forward at top end speed, but who are tapping the heel down on many loading responses. This can be thought of as a retrograde movement and could in a biomechanical way of thinking be considered non-productive. In other words, they are trying to move forward and yet the heel is touching down which is a backwards movement. This point can be argued but that is not the point of this article. The point that we are trying to make is that in order to drop the heel down, and especially if the heel touches, that the runner had better have sufficient ankle rocker/dorsifleixon otherwise the arch may be asked to collapse via excessive pronation (to perform the heel tap) which will drive an internal spin movement when the leg is supposed to be externally rotating to a rigid supinated foot for propulsive toe off. This negative scenario is a huge power leak for a sprinter, or any runner for that matter when they are ramping up speed.
So, why does this happen ? Well, for some it can help to load the posterior mechanism, the gastrocsoleus-achilles complex for conservation and power conversion. It also enables more hip extension and thus more gluteal function. Longer stride means more efficient and greater arm swing which is a huge accessory power source for a sprinter. This also lengthens the stride, they feed off of each other. There are many benefits, if you have sufficient ankle rocker range in the ankle to begin with. In some runners who do not have the requisite ankle rocker range, you may often see the increased foot progression angle and external limb spin and/or the dreaded adductor twist of the heel (aka abductory twist of the foot). These are strategies to get more hip extension and more gluteal function without finding it via the ankle dorsiflexion, where you want to see it. Remember, the body is a brilliant compensatory and substituter. If the body cannot find a range at one joint it will find it at the next proximal or distal joint. And when that loss is at the ankle, motor patterns options dictate you either find it at foot pronation or hip extension.
Maybe, just maybe we should have called this blog article “Can you hold the foot tripod all the way through the stance phase, even through retrograde heel touch down ? If you cannot, trouble could be on the horizon. ” But that is a really dumb title.
Shawn and Ivo
the gait guys