9 ± 3.0 41.1 ± 3.1 42.9 ± 3.1 42.0 ± 3.0   PINP, μg/L         T Group (n = 71) 62.4 ± 3.7 75.1 ± 3.8† 78.7 ± 3.8† 78.7 ± 3.7†   White (n = 45) 62.9 ± 4.5 72.5 ± 4.6 75.1 ± 4.5 77.7 ± 4.5   find more Non-white (n = 26) 61.9 ± 5.9 77.7 ± 6.0 82.4 ± 6.0 79.8 ± 5.9   Bone Resorption Biomarkers TRAP, U/L         T Group (n = 71) 4.3 ± 0.2 4.6 ± 0.2 4.8 ± 0.2† 5.0 ± 0.2†,

‡   White (n = 45) 4.2 ± 0.2 4.7 ± 0.2 4.8 ± 0.2 5.0 ± 0.2   Non-white (n = 26) 4.5 ± 0.3 4.4 ± 0.3 4.8 ± 0.3 5.0 ± 0.3   CTx, μg/L         T Group (n = 71) 1.1 ± 0.1 1.0 ± 0.1 1.2 ± 0.1 RG-7388 molecular weight 1.2 ± 0.1‡   White (n = 45) 1.2 ± 0.1 1.1 ± 0.1 1.1 ± 0.1 1.2 ± 0.1   Non-white (n = 26) 1.0 ± 0.1 1.0 ± 0.1 1.2 ± 0.1 1.1 ± 0.1   *Mean ± SEM; †Different from baseline (P < 0.05); ‡Different from week 3 (P < 0.05); T, main effect of time (P < 0.05). Anthropometrics and associations with vitamin D Status No significant correlations were noted between 25(OH)D levels or biomarkers of inflammation at either baseline or wk 9 (data not shown). Similarly, no significant correlations between 25(OH)D levels and body fat percentage or BMI were documented at baseline in the total study population. In non-whites, however, there was a positive correlation between body fat percentage and 25(OH)D levels at baseline (0.46; P < 0.05). Vitamin D and calcium intake In the total study population, reported

mean daily intakes of vitamin D and calcium were below current RDA levels [22] both before and during BCT (Figure 1). Selleckchem OSI 906 Whites reported consuming more vitamin D during BCT when compared to non-whites (P < 0.05). Neither reported vitamin D nor calcium

intake changed during the course of BCT, regardless of race. Figure 1 Reported vitamin D and calcium intake before and during BCT * *Mean ± SEM; n =71 (white = 45, non-white = 26); †RDA for women 19–30 years of age (Institute of Medicine, 2011); ‡Different from white, P <0.05. Discussion The objective of this longitudinal, observational study was to assess the effects of military training on serum 25(OH)D, PTH levels, bone turnover, MYO10 and vitamin D and calcium intake in female Soldiers during BCT. The major finding was a differential response of serum 25(OH)D during BCT: 25(OH)D levels declined in white volunteers, but increased in non-white volunteers. Serum 25(OH)D levels were greater in white volunteers than non-white volunteers throughout BCT. Additionally, military training resulted in significant increases in PTH and markers of both bone formation and resorption, regardless of race. Estimated dietary intakes of vitamin D and calcium did not meet current RDAs, either before or during BCT. These data confirm earlier findings demonstrating a decline in 25(OH)D levels in white female Soldiers during military training [11], and indicate that non-white Soldiers respond differently.