Everyone "knows" that knees going inwards in a squat is bad, right?

It means the glutes are weak or underactive, and it's not good for the knee.

But is it REALLY?

This episode is a deep dive into the biomechanical, epidemiological, and prospective research on knee alignment during squatting, jumping, running and hopping. Our goal is to answer 2 questions:

1. Does the knee going inwards indicate weak glutes?
2. Is the knee going inwards dangerous?

Links:

• Knees going in during a squat shifts load toward the glute max here
• Knee extensor effort rises with squat depth, hip extensor effort rises with load here
• Same depth-versus-load split found again in a separate study here
• In elite powerlifters, heavier loads shift the work from knee to hip here
• Elite powerlifters hit ~23x bodyweight at the knee joint at 90% of max here
• Weightlifters share load between hip and knee; powerlifters are hip-dominant here
• Sideways knee load in a barbell squat is a consequence of stance width, not a fault here
• Elite weightlifters produce MORE frontal plane hip moment than lower-level lifters, not less here
• Elite powerlifters vary widely in how they load their joints, so there is no one ideal form here
• Lifters who fail a squat above their max show reduced extension and lower muscle activity here
• The knee falls into valgus in ~77% of ACL injuries on video here
• But knee valgus does not predict who goes on to tear an ACL here
• And the drop jump test cannot predict ACL injury in elite players here

Almost all of us foam-roll the ITB and tell clients it's tight.

Here's a richer picture, built from the anatomy: the ITB is a thickening of the fascia that wraps your whole thigh, it behaves as both tendon and ligament, it helps stabilise and lock your knee, and it backs up your ACL, contributing an estimated 13 to 40 percent of the resistance to your shin sliding forward.

Which raises a question about trying to make it "release".

PDF slides to accompany this episode here: https://breathe-edu-downloads.s3.amazonaws.com/IT%20band%20lecture%20slides.pdf

Here's how we know humans are antifragile:

• Yoga is pretty dang safe here
• But if you REALLY want a safe sport, take up breakdancing here (no, seriously!)
• Or Crossfit here
• Knees going in during a squat or lunge doesn't predict injury here
• Plus here are my TWO episodes looking at this topic here and here

But what DOES predict injury:

• Having weak hamstrings here
• Having a weak barbell squat here
• Doing too little for too long, followed by too much too soon here and here

And what protects against injury:

• Strength training is the best injury prevention here and here
• High consistent workloads protect against injury here