Skip to main content
. 2019 Jun 26;122(2):823–832. doi: 10.1152/jn.00138.2019

Fig. 2.

Fig. 2.

Motor unit (MU) discharge frequencies of the superior trapezius (ST) muscle. A, D, and G: scatterplots are of mean MU frequencies and SD (error bars) for each participant dependent on age for 25% of maximal voluntary contraction (MVC; A), 50% of MVC (D), and MVC intensities (G) (n = 20). B, C, E, F, H, and I: kernel density plots representing the distribution of MU discharge frequencies dependent on age group and contraction intensity, with the smoothing bandwidth being scaled to the SD of the smoothing kernel.