Test of two prediction methods for minimum and maximum values of gait kinematics and kinetics data over a range of speeds

Abstract

Background: Minimum and maximum values of gait kinematics and kinetics data are commonly used to quantitatively describe a walking pattern.

Research question: The purposes of this study were to determine the effect of speed on the minimum and maximum values of gait kinematics and kinetics variables and to test two prediction methods for the estimation of these minimum and maximum values at different gait speeds.

Methods: An open dataset with the data of 24 healthy adults (age: 27.6 ± 4.4 years, height: 171.1 ± 10.5 cm, body mass: 68.4 ± 12.2 kg) walking on a treadmill at eight gait speeds was employed in this study. The minimum and maximum angles and moments of the hip, knee, and ankle joints were extracted from speed-dependent prediction curves solely for the minimum and maximum values (PEAK method) and from speed-dependent prediction curves for the entire gait cycle (CYCLE method). The overall error, computed as the root-mean-square error (RMSE), for the minimum and maximum values predicted by these two methods were compared with the experimental true values.

Results: The RMSEs for the joint angles were PEAK: 3.86 ± 1.21°, CYCLE: 3.88 ± 1.18° and for the joint moments were PEAK: 0.129 ± 0.052 Nm/kg, CYCLE: 0.131 ± 0.052 Nm/kg.

Significance: The two prediction methods tested can be used to estimate the minimum and maximum values of biomechanical gait variables at a certain speed.

Keywords: Kinematics; Kinetics; Prediction methods; Walking speed.