The Science of How to Squat
Squats are an important exercise. They protect our ability to perform various actions effectively and without injury: lifting, running, climbing stairs, etc. We often read advice on how to perform squats based on professional opinion or expert consensus.
Interestingly, a group in Switzerland challenged conventional wisdom by measuring how different stances affect joint displacement during squats.1 They used 3D motion-capture and force plates to collect their data. Here are some of their conclusions.
- Knees should be maintained vertically between the malleoli (inner and outer ankle bones) in the frontal plane. This is to reduce risk of injury due to knee displacement.
- Keep the knees back over the ankles. Don’t let them travel forward until they are over the toes.
- Avoid exaggerated foot placement angles in closed chain movements such as the squat. The lowest knee displacement was created by a “wide stance” with toes pointed straight forward. They defined wide stance as twice the distance between the anterior superior iliac spines (aka twice the hip width). This also changes the dynamics of how muscles are activated, shifting more of the strength benefits to the posterior.
- However, the wide stance with toes pointed forward was associated with weaker spine alignment. Resultantly, the authors actually recommend a hip-width stance with toes forward and a wide stance with toes pointed outward 21 degrees.
- Generally, while avoiding extreme positions, the squat does not compromise knee stability. It can be performed correctly even by novice squatters with a low risk of injury due to knee displacement.
Reference
- Lorenzetti S, Ostermann M, Zeidler F, Zimmer P, Jentsch L, List R, Taylor WR, Schellenberg F. How to squat? Effects of various stance widths, foot placement angles and level of experience on knee, hip and trunk motion and loading. BMC Sports Science, Medicine and Rehabilitation. 2018 Dec;10(1):1-1.