Table 2. Co-activated muscle groups during forward or backward locomotion.

There are four co-activated muscle groups during backward and forward locomotion, but the muscles in each group differ in forward versus backward locomotion. Note that backward locomotion is not simple a reverse of the pattern seen in forward locomotion. This represents the most common activation sequences, although there is some variation, particularly during the fastest locomotor velocities.

Forward	Co-activated muscles
F1	2,6,10,11,14,30
F2	3,4,5,9,12,13,18,19,25,26,29
F3	1,8,15,16,17,20,28
F4	21,22,23
Backward	Co-activated muscles
B1	10,15,16,17
B2	1,3,4,6,9,12,13,28
B3	2,5,8,19,20,26,29
B4	11,18,21,22,23,24