Figure 4.

Older adults exhibit impairment in their nervous systems ability to fully activate the knee extensor muscles. This cross-sectional data are the largest study to date examining differences between young and old in central activation and represent data from 46 young (18–32 y) and 46 older (64–84 y) humans. Adapted from Stevens and colleagues (64). Created figure approved by the corresponding author (S. K. Stackhouse).