title: Effects of easy-to-use protein-rich energy bar on energy balance, physical activity and performance during 8 days of sustained physical exertion.
abstract: BACKGROUND
  Previous military studies have shown an energy deficit during a strenuous field training course (TC). This study aimed to determine the effects of energy bar supplementation on energy balance, physical activity (PA), physical performance and well-being and to evaluate ad libitum fluid intake during wintertime 8-day strenuous TC.
  
  
  METHODS
  Twenty-six men (age 20±1 yr.) were randomly divided into two groups: The control group (n = 12) had traditional field rations and the experimental (Ebar) group (n = 14) field rations plus energy bars of 4.1 MJ•day(-1). Energy (EI) and water intake was recorded. Fat-free mass and water loss were measured with deuterium dilution and elimination, respectively. The energy expenditure was calculated using the intake/balance method and energy availability as (EI/estimated basal metabolic rate). PA was monitored using an accelerometer. Physical performance was measured and questionnaires of upper respiratory tract infections (URTI), hunger and mood state were recorded before, during and after TC.
  
  
  RESULTS
  Ebar had a higher EI and energy availability than the controls. However, decreases in body mass and fat mass were similar in both groups representing an energy deficit. No differences were observed between the groups in PA, water balance, URTI symptoms and changes in physical performance and fat-free mass. Ebar felt less hunger after TC than the controls and they had improved positive mood state during the latter part of TC while controls did not. Water deficit associated to higher PA. Furthermore, URTI symptoms and negative mood state associated negatively with energy availability and PA.
  
  
  CONCLUSIONS
  An easy-to-use protein-rich energy bars did not prevent energy deficit nor influence PA during an 8-day TC. The high content of protein in the bars might have induced satiation decreasing energy intake from field rations. PA and energy intake seems to be primarily affected by other factors than energy supplementation such as mood state.
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland. minna.m.tanskanen@jyu.fi
authors.forename: Minna M
authors.initials: MM
authors.lastname: Tanskanen
authors.forename: Klaas R
authors.initials: KR
authors.lastname: Westerterp
authors.forename: Arja L
authors.initials: AL
authors.lastname: Uusitalo
authors.forename: Mustafa
authors.initials: M
authors.lastname: Atalay
authors.forename: Keijo
authors.initials: K
authors.lastname: Häkkinen
authors.forename: Hannu O
authors.initials: HO
authors.lastname: Kinnunen
authors.forename: Heikki
authors.initials: H
authors.lastname: Kyröläinen
mesh_terms: D000273:Adipose Tissue; D000339:Affect / Q000502:physiology; D015992:Body Mass Index; D004044:Dietary Proteins / Q000378:metabolism*; D060766:Drinking Water; D002149:Energy Intake; D004734:Energy Metabolism; D005527:Food, Fortified; D006801:Humans; D006815:Hunger / Q000502:physiology; D008297:Male; D005082:Physical Exertion; D012141:Respiratory Tract Infections / Q000382:microbiology; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D004044:Dietary Proteins; D060766:Drinking Water