The Power of Facilitation: How to supercharge your run.

While running intervalsone morning, something dawned on me. My left knee was hurting from some patellar tracking issues, but only on initial contact and toe off. I generally run with a midfoot strike. I began concentrating on my feet, lifted and spread my toes and voila! my knee pain instantly improved. Very cool, and that is why I am writing this today. 

Without getting bogged down in the mire of quad/hamstring facilitation patterns, lets look at what happened.

I contracted the long extensors of the toes: the extensor digitorum longus and the extensor hallicus longus; the short extensors of my toes: the extensor digitorum brevis, the extensor hallucis brevis: as well as the dorsal interossei.the peroneus longus, brevis and tertius were probably involved as well.

Do you note a central theme here? They are all extensors. So what, you say. Hmmm… 

Lets think about this from a neurological perspective:

In the nervous system, we have 2 principles called convergence and divergence. Convergence is when many neurons synapse on one (or a group of fewer) neuron(s). It takes information and “simplifies” it, making information processing easier or more streamlined. Divergence is the opposite, where one(or a few) neurons synapse on a larger group. It takes information and makes it more complicated, or offers it more options.

In the spinal cord, motor neurons are arranged in sections or “pools” as we like to call them in the gray matter of the cord. These pools receive afferent information  and perform segmental processing (all the info coming in at that spinal cord segment) before the information travels up to higher centers (like the cerebellum and cortex). One of these pools fires the extensor muscles and another fires the flexor muscles.. 

If someone in the movie theater keeps kicking the back of our seat, after a while, you will say (or do) something to try and get them to stop. You have reached the threshold of your patience. Neurons also have a threshold for firing.  If they don’t reach threshold, they don’t fire; to them it is black and white. Stimuli applied to the neuron either takes them closer to or farther from threshold.  When a stimulus takes them closer to firing, we say they are “facilitating” the neuron. If it affects a “pool” of neurons, then that neuronal pool is facilitated. If that pool of neurons happens to fire extensor muscles, then that “extensor pool” is facilitated.

When I consciously fired my extensor muscles, two things happened: 1. Through divergence, I sent information from my brain (fewer neurons in the cortico spinal pathway) to the motor neuron pools of my extensor muscles (larger groups of motor neurons) facilitating them and bringing them closer to threshold for firing and 2. When my extensor muscles fired, they sent that information (via muscle spindles, golgi tendon organs, joint mechnoreceptors, etc) back to my cerebellum, brain stem and cortex (convergence) to monitor and modulate the response.

When I fired my extensor muscles, I facilitated ALL the neuronal pools of ALL the extensors of the foot and lower kinetic chain. This was enough to create balance between my flexors and extensors and normalize my knee mechanics.

If you have followed us for any amount of time, you know that it is often “all about the extensors” and this post exemplifies that fact.

 Next time you are running, have a consciousness of your extensors. Think about lifting and spreading our toes, or consciously not clenching them. Attempt to dorsiflex your ankles and engage your glutes. It just may make your knees feel better!

More Power Leaks: Part 3


Good Morning peoples! A few weeks ago, we introduced posts about potential areas for power leaks. click here for #1, click here for #2

The common areas for leaks are:
great toe dorsiflexion
mm strength test
loss of ankle rocker
loss of knee flexion/extension
loss of hip extension
loss of balance/ proprioception

let’s take a look at a video of the next 2, with Dr Ivo and his partner in SCR, Dr John Asthalter:

Power leak 2: Muscle strength test

you need adequate strength in both the short and long extensors of the toes, for arch integrity, the windlass mechanism as well as appropriate ankle rocker

Common compensations include:

externally rotating the foot and coming off the inside of the great toe. this often causes a callus at the medial aspect of the toe. This places the foot in more pronation (plantar flexion, eversion and abduction) so it is a poorer lever.

lifting the foot (and bending the knee) excessively (knee flexion > 60 degrees) to create clearance of the toes for swing phase. This is sometimes referred to as a steppage gait.

hiking of the hip, again to create clearance for the foot

Power leak 3: ankle rocker

ankle rocker is needed to move the body mass forward in the gravitational plane. It is one of the 3 rockers (for a rocker review, click here).

Compensations for loss of ankle rocker can include:

premature heel rise

shortened step length

excessive pronation through the mid foot

external rotation of the lower extremity and “rolling off” the inside of the great toe

forefoot strike gait

Ivo and Shawn. Giving you the information you need to make informed clinical decisions and build better runners, wherever you go! Spread the word of gait literacy!

How much does your Hallux Extend?

Last week, on Mondays post, we introduced potential areas for power leaks.

The common areas for leaks are:

  • great toe dorsiflexion
  • loss of ankle rocker
  • loss of knee flexion/extension
  • loss of hip extension
  • loss of balance/ proprioception


let’s take a look at a video of the 1st one:

Power leak 1: Great Toe Dorsiflexion

The big toe needs to extend AT LEAST 40 degrees and CLOSER TO 60 degrees for normal walking and running gait. If you do not have that available range of motion, then you will need to “borrow” it from somewhere else.

Common compensations include:

  • externally rotating the foot and coming off the inside of the great toe. this often causes a callus at the medial aspect of the toe. This places the foot in more pronation (plantar flexion, eversion and abduction) so it is a poorer lever.
  • internally rotating the foot and coming off the outside of the foot. This places the foot in more supination ( dorsiflexion, inversion and adduction) and it is therefore a more rigid lever. This often causes tripping or stumbling because of a lack of adequate dorsiflexion of the foot.
  • lifting the foot off the ground and avoiding toe off at terminal stance phase
  • abbreviating the step length to accommodate the amount of available great toe dorsiflexion.

Are YOU losing power? Tune in here for more tips on this series in the coming weeks!

The Gait Guys. Increasing your gait literacy with each and every post.