Spotting Who Might Struggle in Army Boot Camp

A total of 968 male and 450 female recruits began basic training. Their data was collected in the first week of the program. They were measured for fitness, mood, body composition, vitamins and bone strength.

About two thirds of the men passed, while nearly three quarters of the women made it. One in five men and one in three women got injured during training. For the guys, a slower 2.4 km run and more depressive symptoms raised the chance of failing. Low bone mineral density, a past stress fracture, low parathyroid hormone and low collagen breakdown markers also linked to higher injury risk.

For the women, a slower run also meant more trouble passing. Higher total vitamin D levels were tied to failing. Slower running, more alcohol use and lower collagen markers raised the chance of getting hurt.

The computer models could only guess the outcome about two thirds of the time, with scores under 0.68. They were good at saying who would not be selected but missed many true cases. Setting a smarter cut‑off based on the Youden Index helped catch more at‑risk people. Better fitness before training could lower failure and injury rates.