The claimEvidence B · meta-analysis
Knees should never travel past toes
The evidence
Knees travelling past toes is normal squat biomechanics; restricting it shifts load to hips + low back.
The mechanism, in brief
The knee is a disaster zone of marketing claims and folk wisdom. This scene debunks them one by one — each against real evidence.
Sources (4)
- Alentorn-Geli, E., Samuelsson, K., Musahl, V., Green, C. L., Bhandari, M., & Karlsson, J. (2017). The association of recreational and competitive running with hip and knee osteoarthritis: a systematic review and meta-analysis. Journal of Orthopaedic & Sports Physical Therapy, 47(6), 373–390.
- Eckstein, F., Hudelmaier, M., & Putz, R. (2006). The effects of exercise on human articular cartilage. Journal of Anatomy, 208(4), 491–512.
- Liphardt, A. M., Mündermann, A., Andriacchi, T. P., Achtzehn, S., Heer, M., & Mester, J. (2020). Sensitivity of serum concentration of cartilage biomarkers to 21-days of bed rest. Journal of Orthopaedic Research, 38(8), 1788–1795.
- Hartmann, H., Wirth, K., & Klusemann, M. (2013). Analysis of the load on the knee joint and vertebral column with changes in squatting depth and weight load. Sports Medicine, 43(10), 993-1008. Full / deep squats do not increase knee or spine injury risk vs. partial squats when loaded progressively; the 'knees over toes' admonition is biomechanically unsupported.