Injuries and risk factors in a 100-mile (161-km) infantry road march

Background. Light infantry soldiers (N = 218) completed a 161-km cross-coun try march over 5 days carrying an average +/- SD load mass (i.e., the weigh t of all equipment and clothing) of 47 +/- 5 kg. Methods. Prior to the march, height, weight, body fat, and physical fitness (3.2-km run, sit-ups, push ups) were measured. Soldiers completed a demogr aphic questionnaire which included questions on age and tobacco use history . Results. Thirty-six percent (78/218) of the soldiers suffered one or more i njuries. Of the total injuries, 48% presented were blisters and 18% were fo ot pain (not otherwise specified). Eight percent (17/218) of the soldiers w ere unable to complete the march because of injuries. Thirty five percent ( 27/78) of the injured soldiers had 1 or more limited duty days for a total of 69 days. Risk of injury was higher among smokers (risk ratio = 1.8, P = 0.03 compared to nonsmokers) and lower among older soldiers (risk ratio = 3 .2, P = 0.02, <20 years compared to >24 years). Conclusions. Carrying heavy loads over long distances can result in a high injury incidence to the lower body, since 36% of soldiers were injured duri ng the 161-km march. Smoking and younger age (<20 years) were independent r isk factors for injuries. (C) 1999 American Health Foundation and Academic Press.