Composition of Meals Around Exercise Session
Condition: Gastrointestinal Hormones
Study type: Interventional

Summary: 
      This will be a randomised cross-over study where participants will be asked to undergo
      screening session followed by submaximal exercise test and then undergo 2 experimental
      trials, one high CHO trial and another high fat trial, each lasting over 2 days. On Day 1
      participants will consume either high CHO or high fat evening meal and on Day 2 they will be
      exercising for 60 minutes in the fasted state and then consume either high CHO or high fat
      morning meal and then 5 hours after morning meal ad libitum buffet meal. After this, they
      will leave metabolic investigation room and will record all food and drinks consumed during
      the rest of the day. The washout period between the trials will be at least 7 days. Prior to
      each of the experimental trials, participants will be asked to avoid consumption of coffee
      and alcohol for the duration of 2 days. All data collection will all take place in the
      metabolic research unit at New Lister Building (NLB), Glasgow Royal infirmary (GRI).
    

Detailed description: 
      The researcher will enrol eligible participants by means of an advertisement leaflet and word
      of mouth in the campus of the University of Glasgow and other major public areas. Those who
      show interest about the study will be contacted by the researcher who will explain the study
      in detail and will give them a copy of the participant information leaflet. If the
      participant is happy to participate, he will sign an informed consent form and privacy notes.
      Only participants with stable body weight for at least 3 months will be recruited and we will
      exclude those who are on positive or negative energy balance (recent weight gain or loss, ±2
      kg the past month).

      As part of the screening process, each participant will be asked to fill in Physical Activity
      Readiness Questionnaire (PARQ) and Health Screening Questionnaire. Only those who answered
      "no" to all questions in PARQ and were in generally good health will carry on with other
      aspects of the study. These questionnaires will be completed during screening session, which
      will take place at NLB, GRI. Height and body weigh will be measured at the screening session.
      Only those with BMI between 25.0-30 kg/m2 will be invited to participate. Smokers will not be
      recruited. It will be explained that their participation is voluntary, that they may withdraw
      at any point if they wish, and that the data collected will be anonymised. We will thank
      those subjects who have expressed an interest about the study but do not qualify and we will
      explain to them why they need to be excluded. Those who are eligible to participate will be
      enrolled in the trial which will last for 4 weeks and we will measure their height and
      weight.

      Main Experimental Trials:

      The experimental trials will last over 2 days. On day 1 Participants will consume provided
      dinner and on Day2 attend the metabolic research unit at New Lister Building of the Royal
      Infirmary in the fasted state at approximately 09:00 am. An intravenous cannula will be
      placed by a trained phlebotomist upon arrival. This will be used to draw blood samples
      throughout trial. After the collection of the first blood sample, the participant will walk
      on the treadmill at speed and grade corresponding to 55% of their maximal oxygen consumption.
      During exercise, participants will be wearing a heart rate monitor and a face mask connected
      to indirect calorimetry equipment to allow measurements of fat and CHO oxidation Ratings of
      perceived exertion will be recorded at every 10 minutes. Following exercise, participants
      will rest for 60 minutes and then either high CHO or high fat morning meal will be provided.
      Further blood samples will be collected for the duration of 5-hours; in total no more than 70
      ml of blood will be taken during each of the trials. Following the last blood sample
      collection, participants will eat from ad libitum buffet and then leave laboratory and during
      the rest of the day will be recording all food and drink consumed.

      Meal On day 1 dinner meal will provided with either high carbohydrate or high fat meal which
      contains 35% of participants total daily energy intakes. In high CHO trial, meal will consist
      of pasta, meat ball and orange juice. In high fat trial, meals will be based on burger,
      cheese, mushroom, nuts, and butter. On the day 2 and after 60 minutes exercise, participants
      will consume morning meal, providing 30% of their total daily energy intake. In high fat
      trial, morning meals will be based on white bread, peanut butter, nuts, and olives. In high
      CHO trial, meal will consist of oats, skimmed milk, banana and seedless raisins.

      Exercise Tests Participants will conduct a submaximal exercise test to estimate their maximal
      oxygen consumption (V̇O2 max), a marker of cardiorespiratory fitness. During the main
      experimental trials, participants will undergo a 60-minute walking exercise at a
      predetermined work rate corresponding to 55% of their predicted V̇O2 max. Both exercise
      sessions will be conducted on a treadmill and will be at intensity below 85% of maximal HR.
      Heart rate and ratings of perceived exertion will be recorded throughout the test via a heart
      rate monitor.

      Preparation for experimental trials Participants will be asked to record dietary intake for 2
      days prior to the first experimental trial and will be asked to replicate this in the 2 days
      prior to the second experimental trial. Prior to both experimental trials participants will
      be asked to avoid consumption of coffee and alcohol for the duration of 3 days.
    

Intervention name(s): HCHO meals and exercise; LCHO meals and exercise
Intervention type(s): Other; Other
Intervention description(s): Exercise will be conducted after high carbohydrate dinner and prior to high carbohydrate breakfast; Exercise will be conducted after high fat dinner and prior to high fat breakfast
Other intervention name(s): High carbohydrate meals and exercise; Low Carbohydrate and exercise Intervention
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Exercise; Appetite; Gastrointestinal hormones; Macronutrient; Fat oxidation; Thermic effect of food; Energy intake