User blog comment:SilencedSkies/Body Armor: A Comparison./@comment-1440333-20130213151741/@comment-1440333-20130213233326

Again do the research - planty of Space Marines are modeled with raised arms. They have as fluid movement within the armour as they do out of it due to a neural interface that turns the armour into a second skin. Hence how the Marines in the game can run despite the armour weighing a metric ton.