Just kidding…..

I’m sure most of you have heard it before from a trainer, chiropractor, MD, friend, dog walker, scuba diving instructor……..even a physical therapist (cue Sam hanging  his head in shame, embarrassed for the profession)

While doing a lunge or squat do NOT let your knee go over your toe!

Why do people tell us this? Their justification is based on pure snake oil scare tactics. Avoid letting your knee go over your toe because this places too much stress on the knee cap and will cause pain, patella tracking issues, patella tendinitis, your knee cap to explode or your spouse to divorce you.  Problem is…..none of these claims are based on research or real life. No only that, the people that are adamant that this is true are the same people trying to tell you to lift heavy objects like this. Notice the knees!!!!!

This is one of those newsletters where I don’t even need to blow your mind with data to get the point across. However there is one blurb below that refutes the whole knee cap stress issue. First please take a minute to think about things you do on a daily basis. If your knee is not allowed to go over your toe then kiss goodbye the following activities.

Walking downstairs, walking upstairs, walking in general, jumping, landing from said jump, all sports (specifically curling…..yes it’s a sport), hiking, skiing, standing up from a chair, squatting to lift an item off the floor like the picture, bending to tie your shoe, shoveling snow, getting off the toilet, getting on and off the floor to play with a puppy….you get the point

Not only is the warning of knees over toes not realistic to everyday function. It is not supported by evidence. In fact the evidence supports the exact opposite. Training your knees to be comfortable going over your toes including gradually increasing the load has shown to reduce injury!  Yes, reduce injury. Also while performing a deep squat the actual compressive forces on the back of the knee cap reduce once you go past 90 degrees! Nerdy explanation below.

“Based on biomechanical calculations and measurements of cadaver knee joints, the highest retropatellar compressive forces and stresses can be seen at 90°. With increasing flexion, the wrapping effect contributes to an enhanced load distribution and enhanced force transfer with lower retropatellar compressive forces. Additionally, with further flexion of the knee joint a cranial displacement of facet contact areas with continuous enlargement of the retropatellar articulating surface occurs. Both lead to lower retropatellar compressive stresses.”

Hartmann H, Wirth K, Klusemann M. Analysis Of The Load On The Knee Joint And Vertebral Column With Changes In Squatting Depth And Weight Load.Sports Med. 2013 Oct;43(10):993-1008.

So next time someone gives you a hard time about knees over your toes ask them one simple question. Why? And then ask them to demonstrate how they walk down stairs without letting those knees go over the toes. Spoiler, it’s impossible.

Sam Fischer

Sam Fischer

Owner of Choice City Physical Therapy and Doctor of Physical Therapy