Author
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Lukaski, Henry |
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SCRIMGEOUR, ANGUS - USARIEM |
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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 6/20/2009 Publication Date: 3/10/2009 Citation: Lukaski, H.C., Scrimgeour, A.G. 2009. Trace Elements Excluding Iron - Chromium and Zinc. In: Driskell, J.A. Nutrition and Exercise concerns of Middle Age. Baton Rouge, FL:CRC Press. p. 233-250. Interpretive Summary: The percentage of middle-aged US adults who are participating in leisure-time physical activities is growing. These adults also seek credible information about specific supplements that the public press routinely describes as necessary to enable increases in physical performance. Chromium and zinc are two minerals that continue to be highlighted as promoters of physical performance. This book chapter critically reviews the scientific evidence that chromium supplements promote weight and fat loss while increasing muscle mass. It also examines the role that zinc plays in supporting physiological functions needed to enable gains in performance with physical training. The vast majority of research findings indicate that chromium supplementation, particularly as chromium picolinate, neither provides any benefit in promoting weight loss, fat loss or muscle gain in healthy people. Furthermore, chromium supplements do not selectively enhance strength gain during weight training. In contrast, adolescents and adults, who have lowered zinc nutritional status and receive zinc supplements, improve muscle strength and endurance. Similar to chromium, supplementation of otherwise healthy people with zinc has no benefit. In contrast to chromium, some indicators of zinc status are sensitive enough to indicate decreased zinc status and thus indicate individual who would benefit from supplementation. This information will be useful to nutrition and health professional who provide diet information to physically active adolescents and adults. Technical Abstract: The percentage of middle-aged US adults who are participating in leisure-time physical activities is growing. These adults also seek credible information about specific supplements that the public press routinely describes as necessary to enable increases in physical performance. Chromium and zinc are two minerals that continue to be highlighted as promoters of physical performance. This book chapter critically reviews the scientific evidence that chromium supplements promote weight and fat loss while increasing muscle mass. It also examines the role that zinc plays in supporting physiological functions needed to enable gains in performance with physical training. The vast majority of research findings indicate that chromium supplementation, particularly as chromium picolinate, neither provides any benefit in promoting weight loss, fat loss or muscle gain in healthy people. Furthermore, chromium supplements do not selectively enhance strength gain during weight training. In contrast, adolescents and adults, who have lowered zinc nutritional status and receive zinc supplements, improve muscle strength and endurance. Similar to chromium, supplementation of otherwise healthy people with zinc has no benefit. In contrast to chromium, some indicators of zinc status are sensitive enough to indicate decreased zinc status and thus indicate individual who would benefit from supplementation. This information will be useful to nutrition and health professional who provide diet information to physically active adolescents and adults. |
