Fig. 2From: Physiological and psychological neck load imposed by ballistic helmets during simulated military activitiesEffect of total helmet weight on the muscle strain of the four neck muscles during sitting, horizontal lifting, and prone shooting described as changes in %MVC (N = 8) (mean ± SD): The values were averaged for 5 min during each posture. NH = No Helmet; LH = 1.15 kg helmet; HH = 1.5 kg helmet, HH&NVD = 1.5 kg helmet with a night vision device (total weight = 2.1 kg). †P < 0.05 indicates the helmet effects versus NH; Friedman test used for identifying the group differences with a Wilcoxon test as a post-hoc testBack to article page