A protective body armor system for protection against ballistic threats has an armored element such as a vest with front and rear ballistic armor. A long-sleeved shirt is worn beneath the ballistic armor which has a wicking, lightweight, low thermal insulation torso element. Two long sleeves are connected to and extend from the torso element. The torso element is substantially overlain by portions of the armor element, while portions of the sleeve extend beyond the armored element. The shirt has a durable collar connected to the torso element and to the two sleeves. The collar extends upwardly from the armored element. The collar is less resilient than the torso element, and serves to connect the two sleeves and to restrain the garment from undesired distortion.