Functional outcomes
An increase in the scores on the 30-s chair stand test were observed only in the 660 nm group (+ 2.22 times, Comparison of the pre-and post-intervention functional performance-based test for the 808 nm, 660 nm, and the sham control groups. * indicates a statistically significant difference between pre-and post-intervention for the 808 nm group; † indicates a statistically significant difference between the pre-and post-intervention for the 660 nm group; ‡ indicates a statistically significant difference between the pre-and post-intervention of the sham control, and § indicates a statistically significant difference between the 660 nm and the sham control group.