Today’s episode features Adarian Barr, biomechanist and inventor.  Adarian is a unique coach who sees human movement in a fresh new light.  His methods and insight has highlighted the majority of my own learning on sprinting, jumping, throwing and everything in between in the past 2 years, and I’m thrilled to have him back on the show.

Today, Adarian is going to take us on a deep dive into the single most fundamental element of human movement and locomotion, the impulse the body delivers to the ground (or when the ground pushes back on you).  

When we coach athletes in various sporting skills, we will usually start with some sort of big, obvious external position, for example: knees up, or eliminate that backside sprint mechanic.  The problem is that giving these cues, absent from the impulse that facilitated them will throw off an athletes timing and often positioning.  This inevitably leads us on the trail of “keep doing this and eventually you’ll be faster”, but when athletes need to be fast, they’ll just do what they’ve always been doing!  

To this end, understanding the dynamics of the feet, the ankle, the way the body creates impulse into the ground, and how the mechanics of sprinting, jumping and everything else is built around the impulse, we can really start to dig into the core of movement, and why athletes sprint and jump the way they do.  

Today’s episode is brought to you by SimpliFaster, supplier of high-end athletic development tools, such as the Freelap timing system, kBox, Sprint 1080, and more.  

View more podcast episodes at the podcast homepage.

Key Points

Adarian’s history in training the foot

Defining the impulse that projects athletes in sprinting or jumping

How to assess an athlete’s impulse

Impulse in relation to plyometrics and deceleration training

Fundamental differences in athletes with athletes who depress the ankle very little or a lot in running steps

How impulse impacts knee lift in sprinting

Foot steering and how it impacts impulse and direction of force

Adarian Barr Quotes

“My question is, when does the ground push you back.  If you don’t know when the ground is pushing you back, it’s a lost conversation”

“The least amount of movement and the fastest movement is the best (in regards to the impulse and unloading of Achilles)”

“If you can move a joint a quarter inch, faster, you can get a lot more out of it”

“You can’t get a bigger step because (the impulse) is not going to throw you that far”

“When the impulse releases, that’s your max speed”

“If all you do is extend, extend, extend, when it’s time to run and jump, you don’t get the fold up portion”

“Deceleration is already built into the movement”

“The more the heel travels in a negative action towards the ground, the longer it is going to take to be returned to you, and as it returns, you need to make sure the swing leg matches that speed”

“Your block start settings should be based off of the speed and depth of your impulse”

“The four things to the impulse assessment is which way the feet steer, the depth of the shin angle change, the knees track and the magnitude of the impulse… with those four things we can determine how to set you up for any sport”

“If you have a slow and long impulse, you have a high knee lift.  If you have a short and fast impulse, you won’t have as high of knee lift.  The knee rises as the heel drops”

“You don’t want to get rid of backside mechanics, because it’s tied to the impulse”

“(In sprinting) If we are talking about a push the ground person, we do want to get rid of backside mechanics… if we are talking about an impulse person, we don’t want to get rid of backside”

“If you punch the ground, the impulse comes back so fast, you aren’t ready for the next step”

“If the foot is turned out, then the heel must also turn out”

“(with the foot turned out in athletes) the impulse is not going to come from the heel dro...