Knee extensor strength assessed using a vertical squat and a simple geometric model to calculate joint torque: An evaluation of validity and clinical utility.

Aim: We propose a simple method to measure knee extensor muscle strength using a single-legged vertical squat. The purpose of the present study was to assess the validity of this method in comparison with standard methods of measurement.

Methods: A total of 30 healthy adults (mean age 22 years) and 28 healthy older individuals (mean age 69 years) participated in this study.