Effects of Calorie Restriction and Cold Stimuli on Health-related Indicators, Cognitive and Motor Functions
Condition: Calorie Deficiency; Fasting; Cold Exposure
Study type: Interventional

Summary: 
      The goal of this clinical trial was to identify if duration of acute calorie restriction
      (CR)/fasting or combination CR with cold stimuli have any effects on mental and physical
      health-related markers, and to clarify if different fasting strategies have any effect on
      cognitive and motor functioning efficiency in different genders.

      The main questions it aims to answer were:

        -  Does fasting duration have any effect on fasting evoked responses?

        -  Does cold interventions can modulate fasting evoked responses?

        -  Does sex have any effect on acute fasting evoked responses?

      For the first part, participants were randomly classified into 4 groups: two experimental
      groups: 2-days of CR (0 kcal diet) and 6-days of CR (0 kcal diet), and two control groups:
      2-days or 6-days usual diet. For the second part, participants were randomly assigned to
      undergo the following conditions: 2-days of CR with two 10-min whole-body cold-water
      immersions on separate days, 2-days of CR without cold-water immersion, 2-days without CR
      with two 10-min whole-body cold-water immersions on separate days, or 2-days of the usual
      diet without cold-water immersion in a randomized crossover fashion. Changes in
      anthropometric characteristics, perceived stress, metabolism, overall health (total blood
      count, sex hormones, etc.), psycho-emotional state, cognitive and motor functions were
      examined.
    

Detailed description: 
      The goal of this clinical trial was to identify if duration of acute calorie restriction
      (CR)/fasting or combination CR with cold stimuli have any effects on mental and physical
      health-related markers, and to clarify if different fasting strategies have any effect on
      cognitive and motor functioning efficiency in different genders.

      At first study part, participants were randomly classified into 4 groups: two experimental
      groups: 2-days of calorie restriction (CR) (0 kcal diet) and 6-days of CR (0 kcal diet), and
      two control groups: 2-days or 6-days usual diet. In the experimental groups, the participants
      were instructed to follow a prescribed zero-calorie diet with water provided ad libitum over
      a period of 2 or 6 days. In the control groups, the participants were instructed to maintain
      their previous eating habits for 2 or 6 days. Body weight and composition, heart rate
      variability, pulmonary gas exchange, blood pressure, and body temperature were assessed.
      Subsequently, participants completed self-assessment questionnaires, and then saliva samples
      were collected for further cortisol and sex hormones analysis, also capillary and venous
      blood samples were taken for ketone, glucose, insulin, lipid profile, catecholamines,
      brain-derived neurotrophic factor, glucagon, interleukin-10, metabolites of the kynurenines
      pathway and complete blood count concentrations evaluation. Then, the manual dexterity, and
      the cognitive and neuromuscular functions were assessed. The same measurements were repeated
      before each trial, after each trial and after 1 week.

      At second part, participants were randomly assigned to undergo the following conditions:
      2-days of CR with two 10-min whole-body cold-water immersions on separate days, 2-days of CR
      without cold-water immersion, 2-days without CR with two 10-min whole-body cold-water
      immersions on separate days, or 2-days of the usual diet without cold-water immersion in a
      randomized crossover fashion. The same measurements described in first part were repeated
      before each and after each condition.
    

Intervention name(s): 2-days of zero calorie restriction and whole-body cold-water immersion; 6-days of calorie restriction; 2-days of zero calorie restriction without whole-body cold-water immersion; 2-days of usual diet with whole-body cold-water immersion
Intervention type(s): Other; Other; Other; Other
Intervention description(s): The 2-days (48 hours) of zero-calorie restricted diet (with water provided ad libitum) with two whole-body cold-water immersion sessions on separate days. During cooling procedures, the participant was immersed in 14° water bath in semi recumbent position up to the level of the manubrium for 10 min.; The 6-days (144 hours) of prescribed zero-calorie prescribed diet with water provided ad libitum.; 2 days (48 hours) of prescribed zero-calorie diet with water provided ad libitum .; Two whole-body cold-water immersion sessions on separate days. During cooling procedures, the participant was immersed in 14° water bath in semi recumbent position up to the level of the manubrium for 10 min. During intervention, participants were instructed to maintain their previous eating habits.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: This project consisted of two parts. For the first part was used randomized parallel model, and we aimed to investigate fasting duration effect, whereas for the second part was used randomized crossover model and we aimed to investigate if cold exposure can modify fasting evoked effects on health-related indicators, cognition and motor function.
Masking: Single (Investigator)
Primary purpose: Basic Science
Keywords: cognition; motor function; metabolism; young adults; fasting; starvation; men; women; calorie deprivation; stress; kynurines; catecholamines; glucose tolerance; energy expenditure; weight loss