{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T00:20:10Z","timestamp":1792023610955,"version":"4.4.0"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,7,26]],"date-time":"2020-07-26T00:00:00Z","timestamp":1595721600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Training civilians to be soldiers is a challenging task often resulting in musculoskeletal injuries, especially bone stress injuries. This study evaluated bone health biomarkers (P1NP\/CTX) and whey protein or carbohydrate supplementations before and after Army initial entry training (IET). Ninety male IET soldiers participated in this placebo-controlled, double-blind study assessing carbohydrate and whey protein supplementations. Age and fat mass predicted bone formation when controlling for ethnicity, explaining 44% (p &lt; 0.01) of bone formation variations. Age was the only significant predictor of bone resorption (p = 0.02) when controlling for run, fat, and ethnicity, and these factors together explained 32% of the variance in bone resorption during week one (p &lt; 0.01). Vitamin D increased across training (p &lt; 0.01). There was no group by time interaction for supplementation and bone formation (p = 0.75), resorption (p = 0.73), Vitamin D (p = 0.36), or calcium (p = 0.64), indicating no influence of a supplementation on bone biomarkers across training. Age, fitness, fat mass, and ethnicity were important predictors of bone metabolism. The bone resorption\/formation ratio suggests IET soldiers are at risk of stress injuries. Male IET soldiers are mildly to moderately deficient in vitamin D and slightly deficient in calcium throughout training. Whey protein or carbohydrate supplementations did not affect the markers of bone metabolism.<\/jats:p>","DOI":"10.3390\/nu12082225","type":"journal-article","created":{"date-parts":[[2020,7,27]],"date-time":"2020-07-27T04:39:50Z","timestamp":1595824790000},"page":"2225","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Markers of Bone Health and Impact of Whey Protein Supplementation in Army Initial Entry Training Soldiers: A Double-Blind Placebo-Controlled Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5827-0586","authenticated-orcid":false,"given":"JoEllen M.","family":"Sefton","sequence":"first","affiliation":[{"name":"Warrior Research Center, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaitlin D.","family":"Lyons","sequence":"additional","affiliation":[{"name":"Warrior Research Center, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darren T.","family":"Beck","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"},{"name":"Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine (Auburn Campus), Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cody T.","family":"Haun","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"},{"name":"Fitomics, LLC., Birmingham, AL 35294, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew A.","family":"Romero","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petey W.","family":"Mumford","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7696-7398","authenticated-orcid":false,"given":"Paul A.","family":"Roberson","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaelin C.","family":"Young","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"},{"name":"Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine (Auburn Campus), Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7359-5362","authenticated-orcid":false,"given":"Michael D.","family":"Roberts","sequence":"additional","affiliation":[{"name":"Molecular and Applied Sciences Laboratory, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"},{"name":"Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine (Auburn Campus), Auburn, AL 36849-5323, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeremy S.","family":"McAdam","sequence":"additional","affiliation":[{"name":"Warrior Research Center, School of Kinesiology, 301 Wire Road, Auburn University, Auburn, AL 36849-5323, USA"},{"name":"Department of Cell, Developmental, &amp; Integrative Biology, Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1176","DOI":"10.1097\/00005768-199908000-00015","article-title":"Epidemiological patterns of musculoskeletal injuries and physical training","volume":"31","author":"Almeida","year":"1999","journal-title":"Med. 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