Fig. 7

p-values obtained from paired t-tests used to compare the estimation accuracy of muscle forces, as indicated by RMSE values (left) and r values (right), between different optimizations. Initially, RMSE and r values for muscle forces were calculated between the experimental (“Params”) optimization and each of the other optimizations, where results across all calibration trials, legs, and subjects being concatenated and displayed in Table 3. Subsequently, the RMSE and r values for muscle forces from each optimization were compared to the results from every other optimization to determine the statistical significance of the differences in estimation accuracy between each pair of optimizations. All statistical analyses were performed in MATLAB, and the level of statistical significance was set to p < 0.05. A box with green background indicates that the estimation performance for the y-axis optimization was significantly better (lower RMSE values or higher r values) than for the x-axis optimization, while a box with grey background indicates that the estimation performance for the y-axis optimization was significantly worse (higher RMSE values or lower r values) than for the x-axis optimization