Lean Body Mass Response to Higher-protein Diets During Winter Military Training

Effects of Carbohydrate and Protein Supplementation on Whole-body Protein Balance and Skeletal Muscle Mass During Winter Military Training: a Randomized Controlled Trial

The objectives of this study are to: 1) determine effects of a prototype recovery food product providing supplemental energy on whole-body protein balance, skeletal muscle mass, and biomarkers of physiological status and strain during winter military training, and 2) determine the extent to which varying macronutrient composition (protein-based [PRO] versus carbohydrate-based [CHO]) of the food product modulates the physiological consequences to strenuous military training.

Up to 120 Norwegian Soldiers from the 2nd Battalion, Brigade North, Norwegian Army stationed at Skjold Garrison will be enrolled in a 9-day, randomized controlled study. Using dietary analysis, body composition assessments, stable isotope methodologies, basic biochemical techniques, and measures of physiological strain, the effects of supplemental energy in the form of carbohydrate and protein on indices of muscle mass and physiological status will be assessed. We hypothesize that consuming supplemental energy will attenuate the effects of severe energy deficit on inflammation, androgenic hormones, and whole-body protein retention, thereby protecting skeletal muscle mass. We expect that consuming PRO will promote a more favorable recovery than consuming CHO, as indicated by measures of increased whole-body protein synthesis and greater conservation of skeletal muscle mass.

3 Combat rations only per day. No additional experimental food items (those assigned to the active comparator groups will consume isoenergetic carbohydrate and protein-based food products).

Inclusion Criteria: Male and female Norwegian Soldiers aged 18 years or older participating in the 4-day training program. Exclusion Criteria: History of skin irritation (e.g., nickel or adhesive allergy), difficulty swallowing large pills, and allergies to dairy products

Karl JP, Margolis LM, Madslien EH, Murphy NE, Castellani JW, Gundersen Y, Hoke AV, Levangie MW, Kumar R, Chakraborty N, Gautam A, Hammamieh R, Martini S, Montain SJ, Pasiakos SM. Changes in intestinal microbiota composition and metabolism coincide with increased intestinal permeability in young adults under prolonged physiological stress. Am J Physiol Gastrointest Liver Physiol. 2017 Jun 1;312(6):G559-G571. doi: 10.1152/ajpgi.00066.2017. Epub 2017 Mar 23.

Margolis LM, Murphy NE, Martini S, Gundersen Y, Castellani JW, Karl JP, Carrigan CT, Teien HK, Madslien EH, Montain SJ, Pasiakos SM. Effects of Supplemental Energy on Protein Balance during 4-d Arctic Military Training. Med Sci Sports Exerc. 2016 Aug;48(8):1604-12. doi: 10.1249/MSS.0000000000000944.

Pasiakos SM, Margolis LM, Murphy NE, McClung HL, Martini S, Gundersen Y, Castellani JW, Karl JP, Teien HK, Madslien EH, Stenberg PH, Young AJ, Montain SJ, McClung JP. Effects of exercise mode, energy, and macronutrient interventions on inflammation during military training. Physiol Rep. 2016 Jun;4(11):e12820. doi: 10.14814/phy2.12820.