In:
Applied Physiology, Nutrition, and Metabolism, Canadian Science Publishing, Vol. 39, No. 12 ( 2014-12), p. 1395-1401
Abstract:
Physiological consequences of winter military operations are not well described. This study examined Norwegian soldiers (n = 21 males) participating in a physically demanding winter training program to evaluate whether short-term military training alters energy and whole-body protein balance, muscle damage, soreness, and performance. Energy expenditure (D 2 18 O) and intake were measured daily, and postabsorptive whole-body protein turnover ([ 15 N]-glycine), muscle damage, soreness, and performance (vertical jump) were assessed at baseline, following a 4-day, military task training phase (MTT) and after a 3-day, 54-km ski march (SKI). Energy intake (kcal·day −1 ) increased (P 〈 0.01) from (mean ± SD (95% confidence interval)) 3098 ± 236 (2985, 3212) during MTT to 3461 ± 586 (3178, 3743) during SKI, while protein (g·kg −1 ·day −1 ) intake remained constant (MTT, 1.59 ± 0.33 (1.51, 1.66); and SKI, 1.71 ± 0.55 (1.58, 1.85)). Energy expenditure increased (P 〈 0.05) during SKI (6851 ± 562 (6580, 7122)) compared with MTT (5480 ± 389 (5293, 5668)) and exceeded energy intake. Protein flux, synthesis, and breakdown were all increased (P 〈 0.05) 24%, 18%, and 27%, respectively, during SKI compared with baseline and MTT. Whole-body protein balance was lower (P 〈 0.05) during SKI (–1.41 ± 1.11 (–1.98, –0.84) g·kg −1 ·10 h) than MTT and baseline. Muscle damage and soreness increased and performance decreased progressively (P 〈 0.05). The physiological consequences observed during short-term winter military training provide the basis for future studies to evaluate nutritional strategies that attenuate protein loss and sustain performance during severe energy deficits.
Type of Medium:
Online Resource
ISSN:
1715-5312
,
1715-5320
DOI:
10.1139/apnm-2014-0212
Language:
English
Publisher:
Canadian Science Publishing
Publication Date:
2014
SSG:
31
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