Physical and psychological stress on Warfighters during training and operational missions can suppress immune responsiveness. Skin wound healing models can be used to detect changes in immune function. The goals of this research are to: 1) quantify the impact of an operational stressor (i.e., sleep restriction) on suction blister immune response and skin barrier restoration; and, 2) test the influence of nutrition intervention(s) on immune response and skin barrier restoration consequent to an operational stressor. Research will be conducted in a laboratory environment using male and female Soldiers from the human research participant detachment (NSRDEC), NSRDEC and/or USARIEM. Recently, the investigators lab assessed the test-retest reliability of a suction blister model by creating eight suction blisters on participants' left and right forearms, and sampling blister fluid and skin barrier restoration (12-06H), which will serve as one of the control groups (Group 1, N = 15) for the study described herein. Participants in the study described herein (Groups 2-4, n = ~60) will be exposed to ~50 hours of sleep restriction , after which time eight suction blisters will be induced on one forearm and immune responsiveness and skin barrier restoration time recorded. Participants will receive no nutrition intervention (Group 2), an immune-enhancing beverage and additional protein (1.2 g protein per kg body weight versus 0.8 g protein per kg body weight) (Group 3) or probiotics (Group 4), during and after sleep restriction to determine if nutritional approaches attenuate the loss of immune responsiveness. The results of this study will provide insight into whether nutritional supplementation approaches confer immune recovery. The investigators hypothesize that the suction blister immune response (during the 24 hours following blister induction) and time to skin barrier restoration will degrade after an imposed stress which includes~50 hours of wakefulness and constrained living; and, a diet supplemented with either protein and a multi-nutrient nutritional supplement OR probiotics will attenuate the decrements in suction blister immune responsiveness (during the 24 hours following blister induction) and time to skin barrier restoration in response to ~50 hours of sustained wakefulness and constrained living.
Physical and psychological stress on military personnel during training and operational missions can suppress immune function. Creating superficial skin wounds via suction blisters can be used to detect changes in immune function. The goals of this research are to: 1) identify changes in immune function (blood measures and healing time of skin wounds) in response to sleep restriction; and, 2) test the influence of a multi-nutrient beverage and healthy bacteria (i.e., probiotics) on immune function (blood measures and healing time of skin wounds) in response to sleep restriction.