TABLE 4-8 Multivariate Analysis of Risk Factors for Injury during Army Basic Combat Training, Fort Jackson, South Carolina, 1998-2000


Injury Risk Ratio (95% CI)




Low cardiorespiratory fitness



1 quartile decrease in run time

1.11 (1.07, 1.15)

1.13 (1.09, 1.17)

Body fatness



1 quartile increase in BMI

1.00 (0.96, 1.04)

0.97 (0.93, 1.00)

Gender (female versus male)

2.25 (2.07, 2.45)

2.26 (2.08, 2.45)

NOTE: CI = confidence interval.

aControlling for the other variables listed in this table.

SOURCE: Jones, Darakjy, and Knapik (2004). U.S. Army Center for Health Promotion and Preventive Medicine. Previously unpublished data from samples of male and female trainees at Fort Jackson, South Carolina. See Figure 4-3 for cutpoints used to define categories.

These results underscore the importance of strengthening the role of fitness testing (at least for cardiorespiratory fitness) in current recruitment procedures. Potentially, fitness could be improved by introducing a new standard based on a simple test of physical fitness. The Accessions Medical Standards Analysis and Research Activity has experimented with the introduction of a simple step test into the MEPS (Krauss, 2004).


There is clear evidence that preservice fitness is directly related to attrition. In a longitudinal study of Army recruits who entered military service in 1999, the physical fitness levels of recruits when arriving at basic training predicted attrition both during training and years later, in operational units.2 Specifically, recruits who passed the Army’s physical fitness test both very early in training and later in training had an 18.9 percent attrition rate from their operational unit, whereas those who failed the test both early and later in training had a 26 percent attrition rate from


Personal communication from Dan Putka, HumRRO, 2005, based on reanalyses of data collected for the Army Research Institute’s Project First Term.

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