The Critical Link in Speed: Athletic Lower Leg Development

Variability is the ability to move, and use, the ankle in an expanded range of motion. Athletes who spend all practice with taped ankles, and wear clunky shoes all the time will have extremely low variability, and movement ability.

What is the most important component of getting athletes faster?
Getting stronger?
Having more functional glutes?
Knee drive?

An essential component of speed lies not just in what happens above the knee, but below it. The two factor model of sprinting by Ken Clark has shown that the lower leg is a large component of the total vertical ground reaction force during sprinting, specifically the vertical acceleration of the ankle.

According to French speed expert and researcher, JB Morin, ankle strength is a huge portion of the speed component.

JB States:
“I see things as generating power, and then transmitting it effectively onto the ground. If you have an imbalance, if you are able to transmit very well forces onto the ground because of ankle strength, but you don’t generate power, then you have something missing. If you are able to generate a huge power with the hip extensors, but the transmission of the foot is weak, then it is useless as well”
(More info: https://www.just-fly-sports.com/podcast-12-jb-morin/)

So what should we be looking at, and thinking about when it comes to the feet and speed? Just saying “get the foot stronger” through doing things like calf and tibial raises is a little reductionist, and for performance gains a primer to the function of the foot is required. The list below gives some insight into the “layers” of the foot, and how it relates to athletic speed and power.

• Load to explode
• Pronation, supination and the big toe
• Crossover gait and foot spin
• Elastic power of the lower leg
• Sensory qualities of the foot

Much of what I’ve learned about the athletic foot, I must credit to sprint coaches Chris Korfist and Adarian “AK” Barr. Today, I’ll expand on the first piece of the foot equation I’ve listed, which is loading and exploding.

Loading and Exploding

To explode off the big toe (the ultimate goal of athletic speed), one must load the foot first.

Supination (loading pinky toe side of foot) is associated with loading, while pronation (loading the big toe side) is associated with exploding. Most weight room movements, from a load-explode paradigm, teach athletes how to load well as far as the feet are concerned (squatting and RFESS’s are load biased), but aren’t the best at teaching athletes to explode well, and can even be counter-productive if overly emphasized, with the feet ignored.

By super setting weight room movements with (preferably barefoot) plyometric work and supplementary barefoot training, the foot can be more fully integrated into athletic movement. If your facility rules allow, doing appropriate barefoot strength training is huge from a connection perspective, as well as offering the athlete a greater sensory link to the ground. One of my favorite strength movements for this is a hex bar deadlift done barefoot and with high handles or off the pins. The high vertical force of the movement also delivers a huge sensory load to the feet.

In order to load the foot well in athletic positions (team sport cuts, vertical jumps off the run, etc.) the concept of variability is key.

Variability is the ability to move, and use, the ankle in an expanded range of motion. Athletes who spend all practice with taped ankles, and wear clunky shoes all the time will have extremely low variability, and movement ability. Watch Michael Jordan driving the lane, or on the pure human movement end, the ankle of a high-level high jumper for an example of just how important have mobility, and strength in that mobility is for athletes to load to the foot in athletic positions, and reach their highest potential.


MJ is a great example of an athlete with great ankle strength in mobility.

 

We also see a high amount of ankle variability in some great jumpers from track and field. See :40 of the video with one of the best high jumpers in USA high school history.

 

One of the best ways to improve this mobility and function, which can lead to better movement on the court and field, as well as preventing injuries, not only in the ankle, but upstream, is Dick Hartzell’s jump stretch band series work.

 

Although this article is not exhaustive in the least, I hope it clues you into two aspects of how simple tweaks to your typical preparation routine can go a long way in improving the “lower aspect” of the two-factor model in building better athletes.