Troops can move at double speed. If they start their move within 8" of an enemy, they must pass a Leadership test to do so.

Marching troops move at twice their normal Movement rate. A unit on the march is not permitted to reform, as this would disrupt its movement, nor is it allowed to move backwards or to the side. It can wheel as normal, as you might imagine a column of troops would in order to follow a road, for example.

It is also worth noting that a unit that has marched in the Movement phase cannot shoot missile weapons during the Shooting phase.