The Fallacy of Keeping the Knee Over the Middle of the Foot

Apr 4, 2016 | by Gray Institute

The Fallacy of Keeping the Knee Over the Middle of the Foot During Functional Training & Rehabilitation

As practitioners of movement it is likely that all of us have heard that we should train clients to keep their knees over the second toe (middle of the foot).

Many of us have taken this admonition to heart, and emphasized this in our programs for squatting, lunging, jumping, and even running.

This is done in spite of our own observations, as well as research studies, that indicate this is not part of normal function.

Not Part of Normal Function

So if keeping the knee “stuck” in the sagittal plane is not part of function, why did we “buy into” this approach?

We all recognize that knee injuries (ACL, MCL, Patello-femoral) have great individual and societal ramifications. We also know that injuries often occur when the knee “dives in” with too much frontal plane valgus and transverse plane rotation.

So if excessive amounts of these motions results in injury, it would be logical to try to eliminate them by keeping the knee over the middle of the foot.

Well-respected surgeons and researchers designed programs to “help us” eliminate these motions. Dr. Gary Gray describes this as a bad decision by people whose “heart was in the right place”, but did not understand the three-dimensional biomechanics of function.

Too little of these motions is just as bad as too much.

Why It’s a Bad Idea

Let’s consider the reasons keeping the knee over the middle of the foot is a bad idea:

  1. It doesn’t happen in real function.
  2. Training requires conscious control which is not feasible during sports activities
  3. When consciously achieved, the motion in the frontal and transverse planes, which is needed to proprioceptively activate the powerful hip muscles, is lost.
  4. The motion of the subtalar joint must also be reduced / eliminated to keep the knee over the middle of the foot, which alters locomotor biomechanics.

There is no doubt that functional training can reduce knee injuries, and no one would argue that reducing these motions from excessive to “normal” is a bad thing.

But the “normal” amount of frontal and transverse plane knee motion depends on what the person is doing.

The Truths of Human Movement

Practitioners of Applied Functional Science® (AFS) design strategies based on the Principles (truths) of human movement to progress clients through a logical progression of movements.  The goal is to convert these potentially harmful motions at the knee into a critical part of any rehabilitation or injury prevention program.

The AFS® practitioner …

1. Recognizes the knee motions are driven from and controlled by the hip, foot, arms and trunk.

  1. Performs an assessment that determines the successful and not so successful movements in 3 planes of motion using the hands, feet , and pelvis to create motion
  2. Identifies where there is dysfunction that is allowing excessive motion or causing too little motion
  3. Starts movement training where the client is successful
  4. Designs strategies that take advantage of the chain reaction biomechanics
  5. Tweaks the movements to add more resources to the task to ensure success
  6. Increases the task demands as the client demonstrates success
  7. Progresses the program by tweaking out resources based on the biomechanics of the functional activity while maintaining successful execution

This is the Principles – Strategies – Techniques process of AFS. The logical strategies that are derived from the Principles of human movement are the same for rehabilitation, performance training, and injury prevention.  The strategies determine which of the thousand of possible movements are best for this specific client at this time.  The resulting techniques/movements are easily tweaked to address deficits of flexibility, strength, balance, power, and endurance.

If you want to learn the science behind the P-S-T process

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