These really do not promote the development of subtle fighting skills that are difficult to train, and are for small / weak people to use against larger. Much better off taking the largest and toughest young men, teaching them simple and easily trained skills, and putting your resources into developing methods for organizing and directing fighters, and working out how to feed and equip them.
Which is pretty much the history of mass warfare. Cannon fodder. Put the young, dumb, big ones in front. And the let old, experienced, tricky ones bring up the rear. Or run away if things go poorly...