The Multivariate Largest Lyapunov Exponent as an Age-Related Metric of Quiet Standing Balance

Figure 3

The results of PSD analysis. A PSD analysis of the frequency domain was carried out. The results of one typical young subject and one typical old subject are plotted, where ten seconds of the four typical traces obtained for COP and the sagittal kinematics is on the left, together with the corresponding PSD on the right. (a), (c), (e), (g), (i), (k), (m), and (o) are the time series and (b), (d), (f), (h), (j), (l), (n), and (p) are their corresponding PSD plots.

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