{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T04:33:18Z","timestamp":1791261198157,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2023,12,18]],"date-time":"2023-12-18T00:00:00Z","timestamp":1702857600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Wisconsin-La Crosse"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: The purpose of this study was to assess the effects of protein and carbohydrate supplementation, with and without creatine, on occupational performance in firefighters. Methods: Using a randomized, double-blind approach, thirty male firefighters (age: 34.4 \u00b1 8.4 yrs., height: 1.82 \u00b1 0.07 m; weight: 88.6 \u00b1 12.5 kg; BF%: 17.2 \u00b1 5.8%) were randomized to receive either (A.) 25 g of whey protein isolate + 25 g of carbohydrate powder (ProCarb group); or (B.) ProCarb + 5 g of creatine (Creatine group) in a double-blind fashion over a period of 21\u201326 days (depending on shift rotations) to evaluate the impact of supplementation on occupation-specific performance. At baseline and following supplementation, firefighters completed a battery of tests. These tests included an aerobic speed test on an air-braked cycle ergometer followed by the hose carry, body drag, stair climb, and Keiser sled hammer for time. Results: No significant differences in measures of performance were observed at baseline (p &gt; 0.05). There was a significant main effect for time observed for rescue, stair climb, total time to completion, and time trial performance (p &lt; 0.05). There was a significant group \u00d7 time (p &lt; 0.05) interaction for rescue and forcible entry. Independent sample t-tests indicated that the Creatine group experienced a greater reduction (from baseline) in completion time for the rescue (1.78 \u00b1 0.57 s, 95% CI: 0.61, 2.95 s, p = 0.004) and forcible entry (2.66 \u00b1 0.97 s, 95% CI: 0.68, 4.65 s, p = 0.01) tests compared to the ProCarb group. No significant group \u00d7 time interactions were observed for the hose line advance, stair climb, total time to completion, and time trial performance (p &gt; 0.05). Conclusions: The addition of supplemental creatine to a protein and carbohydrate supplement to the diet of career firefighters throughout a three week period improves occupational performance in firefighters in specific areas of high-intensity, repetitive actions.<\/jats:p>","DOI":"10.3390\/nu15245134","type":"journal-article","created":{"date-parts":[[2023,12,18]],"date-time":"2023-12-18T08:55:29Z","timestamp":1702889729000},"page":"5134","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["The Effects of Protein and Carbohydrate Supplementation, with and without Creatine, on Occupational Performance in Firefighters"],"prefix":"10.3390","volume":"15","author":[{"given":"Kaia","family":"Elstad","sequence":"first","affiliation":[{"name":"Exercise & Sport Science Department, University of Wisconsin-La Crosse, La Crosse, WI 54601, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Conley","family":"Malone","sequence":"additional","affiliation":[{"name":"Medicine & Health Sciences, Des Moines University, Des Moines, IA 50312, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel","family":"Luedke","sequence":"additional","affiliation":[{"name":"Sports Medicine Department, Mayo Clinic Health System, La Crosse, WI 54650, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salvador J.","family":"Jaime","sequence":"additional","affiliation":[{"name":"Exercise & Sport Science Department, University of Wisconsin-La Crosse, La Crosse, WI 54601, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ward C.","family":"Dobbs","sequence":"additional","affiliation":[{"name":"Exercise & Sport Science Department, University of Wisconsin-La Crosse, La Crosse, WI 54601, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Almonroeder","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Trine University, Angola, IN 46703, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0458-7294","authenticated-orcid":false,"given":"Chad M.","family":"Kerksick","sequence":"additional","affiliation":[{"name":"Sports Medicine Department, Mayo Clinic Health System, La Crosse, WI 54650, USA"},{"name":"Exercise and Performance Nutrition Laboratory, Department of Kinesiology, Lindenwood University, St. Charles, MO 63301, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam","family":"Markert","sequence":"additional","affiliation":[{"name":"La Crosse Fire Department, City of La Crosse, La Crosse, WI 54601, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6651-5096","authenticated-orcid":false,"given":"Andrew R.","family":"Jagim","sequence":"additional","affiliation":[{"name":"Exercise & Sport Science Department, University of Wisconsin-La Crosse, La Crosse, WI 54601, USA"},{"name":"Sports Medicine Department, Mayo Clinic Health System, La Crosse, WI 54650, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1519\/JSC.0b013e31829b54da","article-title":"Firefighter health and fitness assessment: A call to action","volume":"28","author":"Storer","year":"2014","journal-title":"J. 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