Nancy E Murphy1, Christopher T Carrigan1, J Philip Karl1, Stefan M Pasiakos1, Lee M Margolis2,3. 1. Military Nutrition Division, US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Bldg. 42, Natick, MA, 01760, USA. 2. Military Nutrition Division, US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Bldg. 42, Natick, MA, 01760, USA. lee.m.margolis.ctr@mail.mil. 3. Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA. lee.m.margolis.ctr@mail.mil.
Abstract
BACKGROUND: Negative energy balance (EB) is common during military operations, diminishing body mass and physical performance. However, the magnitude of negative EB where performance would still be maintained is not well defined. OBJECTIVE: Our objective was to explore relationships between EB and physical performance during military operations and define an acceptable negative EB threshold where performance may be maintained. METHODS: A systematic search was performed for studies that measured EB and physical performance during military training. A total of 632 articles and technical reports were screened. Lower-body power and strength were the most common performance tests across investigations and were used as physical performance outcomes. Data were extracted from nine eligible studies containing 15 independent subgroups. Meta-regression assessed changes in performance in relation to study duration (days), average daily EB, and total EB (daily EB × duration). RESULTS: Changes in physical performance were not associated with average daily EB or training duration. Total EB was associated with changes in lower-body power (r2 = 0.764, P < 0.001) and strength (r2 = 0.836, P < 0.001) independently and combined (r2 = 0.454, P = 0.002). Predictive equations generated from the meta-regression indicated that, for a zero to small (2%) decline in performance, total EB should be limited to - 5686 to - 19,109 kcal, for an entire operation, whereas total EB of - 39,243 to - 59,377 kcal will result in moderate (7%) to large (10%) declines in performance. CONCLUSION: These data demonstrated that greater total negative EB is associated with declines in lower-body performance during military operations.
BACKGROUND: Negative energy balance (EB) is common during military operations, diminishing body mass and physical performance. However, the magnitude of negative EB where performance would still be maintained is not well defined. OBJECTIVE: Our objective was to explore relationships between EB and physical performance during military operations and define an acceptable negative EB threshold where performance may be maintained. METHODS: A systematic search was performed for studies that measured EB and physical performance during military training. A total of 632 articles and technical reports were screened. Lower-body power and strength were the most common performance tests across investigations and were used as physical performance outcomes. Data were extracted from nine eligible studies containing 15 independent subgroups. Meta-regression assessed changes in performance in relation to study duration (days), average daily EB, and total EB (daily EB × duration). RESULTS: Changes in physical performance were not associated with average daily EB or training duration. Total EB was associated with changes in lower-body power (r2 = 0.764, P < 0.001) and strength (r2 = 0.836, P < 0.001) independently and combined (r2 = 0.454, P = 0.002). Predictive equations generated from the meta-regression indicated that, for a zero to small (2%) decline in performance, total EB should be limited to - 5686 to - 19,109 kcal, for an entire operation, whereas total EB of - 39,243 to - 59,377 kcal will result in moderate (7%) to large (10%) declines in performance. CONCLUSION: These data demonstrated that greater total negative EB is associated with declines in lower-body performance during military operations.
Authors: Lee M Margolis; Nancy E Murphy; Svein Martini; Yngvar Gundersen; John W Castellani; J Philip Karl; Christopher T Carrigan; Hilde-Kristin Teien; Elisabeth-Henie Madslien; Scott J Montain; Stefan M Pasiakos Journal: Med Sci Sports Exerc Date: 2016-08 Impact factor: 5.411
Authors: Lee M Margolis; Nancy E Murphy; Svein Martini; Marissa G Spitz; Ingjerd Thrane; Susan M McGraw; Janet-Martha Blatny; John W Castellani; Jennifer C Rood; Andrew J Young; Scott J Montain; Yngvar Gundersen; Stefan M Pasiakos Journal: Appl Physiol Nutr Metab Date: 2014-12 Impact factor: 2.665
Authors: Alyssa N Varanoske; Melissa N Harris; Callie Hebert; Emily E Howard; Neil M Johannsen; Steven B Heymsfield; Frank L Greenway; Lee M Margolis; Harris R Lieberman; Robbie A Beyl; David D Church; Arny A Ferrando; Stefan M Pasiakos; Jennifer C Rood Journal: J Appl Physiol (1985) Date: 2022-07-07
Authors: Drew E Gonzalez; Matthew J McAllister; Hunter S Waldman; Arny A Ferrando; Jill Joyce; Nicholas D Barringer; J Jay Dawes; Adam J Kieffer; Travis Harvey; Chad M Kerksick; Jeffrey R Stout; Tim N Ziegenfuss; Annette Zapp; Jamie L Tartar; Jeffery L Heileson; Trisha A VanDusseldorp; Douglas S Kalman; Bill I Campbell; Jose Antonio; Richard B Kreider Journal: J Int Soc Sports Nutr Date: 2022-06-23 Impact factor: 4.948
Authors: J Philip Karl; Claire E Berryman; Melissa N Harris; Harris R Lieberman; Kishore M Gadde; Jennifer C Rood; Stefan M Pasiakos Journal: J Endocr Soc Date: 2020-03-03
Authors: Stefan M Pasiakos; Claire E Berryman; J Philip Karl; Harris R Lieberman; Jeb S Orr; Lee M Margolis; John A Caldwell; Andrew J Young; Monty A Montano; William J Evans; Oshin Vartanian; Owen T Carmichael; Kishore M Gadde; Neil M Johannsen; Robbie A Beyl; Melissa N Harris; Jennifer C Rood Journal: EBioMedicine Date: 2019-07-27 Impact factor: 8.143
Authors: Alyssa N Varanoske; Melissa N Harris; Callie Hebert; Emily E Howard; Neil M Johannsen; Steven B Heymsfield; Frank L Greenway; Lee M Margolis; Harris R Lieberman; David D Church; Arny A Ferrando; Jennifer C Rood; Stefan M Pasiakos Journal: Contemp Clin Trials Commun Date: 2021-07-03