Comparison of the physical fitness of men and women entering the U.S. army: 1978-1998

To compare the physical fitness levels of recruits entering the U.S. Army in 1998 to those entering in 1978 and 1983. In 1998, 182 men and 168 women were tested before beginning basic training at Fort Jackson, SC. The measurements were 1) skin-fold estimation of percent body fat (%BF); 2) maximum oxygen uptake by treadmill running (VO2max); and 3) upper-body (UB), lower-body (LB), and upright pulling (UP) isometric strength. These data were compared to data from basic trainees at Fort Jackson in 1978 (skin folds, VO2max, UB, and LB) and 1983 (skin folds and UP). Body weight (BW) of 1998 recruits was greater (P < 0.05) than 1978 recruits (men, 12%; women, 6%) and 1983 recruits (men, 8%; women, 7%). %BF of 1998 recruits was greater (P < 0.05) than 1978 recruits (men, 15%; women, 5%) and 1983 recruits (men, 15%; women, 17%). The 1998 men had more fat-free mass (FFM) (P < 0.05) than men in 1978 (8%) or 1983 (5%), whereas 1998 women were only different from those measured in 1978 (4%, P < 0.05). The VO2max of men (50.6 +/- 6.2 mL x kg(-1) x min(-1)) was equivalent to men in 1978, whereas that of women (39.7 +/- 5.2 mL x kg(-1) x min(-1)) was 6% greater (P < 0.05). The 1998 recruits were stronger (P < 0.05) on all measures of muscle strength than recruits measured in 1978 (men, UB = 16%, LB = 12%; women, UB = 18%, LB = 6%) and 1983 (men, UP = 7%; women, UP = 6%). The aerobic capacity, muscle strength, and FFM of 1998 recruits is comparable to or greater than that of 1978 and 1983 recruits; however, 1998 recruits tended to have more BW and a greater %BF.