Walker participated in the 2012 Rising Stars Challenge during All-Star Weekend.

Aboard these Space Shuttle missions Walker also performed early protein crystal growth experiments and participated as a test subject in numerous medical studies.

Walker crossed the picket lines and participated in spring training during the 1994 Major League Baseball strike as a replacement player.

Walker accepts and participates in several interviews.

Walker has participated in a variety of sports including football, Olympic bobsledding, track and field, taekwondo, and ballet dancing.

Walker also participated in the temperance movement.

Walker also helped organize and participated in the 1963 March on Washington.

During the winter of 1862 and 1863, Walker participated in the thrusts against Haines Bluff and Arkansas Post.

Walker then participated in the Battle of Molino del Rey in early September and was once more wounded, this time in the back.

Walker then participated in the Vicksburg Campaign that summer in Johnston's command.