Supplementing an energy adequate, higher protein diet with protein does not enhance fat-free mass restoration after short-term severe negative energy balance
Abstract
Negative energy balance during military operations can be severe and result in significant reductions in fat-free mass (FFM). Consuming supplemental high-quality protein following such military operations may accelerate restoration of FFM. Body composition (dual-energy X-ray absorptiometry) and whole body protein turnover (single-pool [15N]alanine method) were determined before (PRE) and after 7 days (POST) of severe negative energy balance during military training in 63 male US Marines (means ± SD, 25 ± 3 yr, 84 ± 9 kg). After POST measures were collected, volunteers were randomized to receive higher protein (HIGH: 1,103 kcal/day, 133 g protein/day), moderate protein (MOD: 974 kcal/day, 84 g protein/day), or carbohydrate-based low protein control (CON: 1,042 kcal/day, 7 g protein/day) supplements, in addition to a self-selected, ad libitum diet, for the 27-day intervention (REFED). Measurements were repeated POST-REFED. POST total body mass (TBM; −5.8 ± 1.0 kg, −7.0%), FFM (−3.1 ± 1.6 kg, −4.7%), and net protein balance (−1.7 ± 1.1 g protein·kg−1·day−1) were lower and proteolysis (1.1 ± 1.9 g protein·kg−1·day−1) was higher compared with PRE ( P −1·day−1). However, diets differed by protein intake due to supplementation (CON: 2.0 ± 0.4, MOD: 3.2 ± 0.7, and HIGH: 3.5 ± 0.7 g·kg−1·day−1; P −1·day−1) and gained TBM (5.9 ± 1.7 kg, 7.8%) and FFM (3.6 ± 1.8 kg, 5.7%) POST-REFED compared with POST ( P < 0.05). Supplementing ad libitum, energy-adequate, higher protein diets with additional protein may not be necessary to restore FFM after short-term severe negative energy balance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 01, 2017
- Source ID
- 10.1152/japplphysiol.01039.2016
Entities
People
- A. A. Ferrando
- C. E. Berryman
- E. K. Farina
- H. L. Mcclung
- H. R. Lieberman
- J. J. Sepowitz
- J. P. Mcclung
- Stefan M. Pasiakos
Organizations
- Oak Ridge Institute for Science and Education
- United States Army Medical Research and Development Command
- United States Army Research Institute of Environmental Medicine
- University of Arkansas for Medical Sciences