Maple Products and Exercise Performance
Condition: Carbohydrate Ingestion; Fuel Selection; Athletic Performance
Study type: Interventional

Summary: 
      The purpose of this study is to compare the acute metabolic responses and time-trial
      performance following the ingestion of carbohydrate solutions containing either maple syrup,
      maple sap, corn syrup, a commercial sport drink or water.
    

Detailed description: 
      The study will require 4 meetings for each subject: a 30-minute meeting to explain the
      project; a meeting of 2 hours (glucose tolerance test, at rest); a one-hour meeting (maximum
      oxygen consumption test (VO2max) during an exercise conducted on an electromagnetically
      braked cycle ergometer, and a meeting of about 4 hours for experimentation (120-min exercise
      on a stationary bicycle with ingestion of a solution carbohydrates or sweetened water, and a
      20-km time trial).

      Visit #1 - Pre-participation (screening visit) Following an initial contact by phone or
      email, the subject will be invited to individual meetings which will last about 15 minutes.
      During the meeting, one of the project managers will check the eligibility of the potential
      subject in the study and, if eligible, will present him the details of the protocol
      specifying the discomforts and risks involved. The participant will be required to fill a
      Physical Activity Readiness Questionnaire (PAR-Q) and will be given a copy of the consent
      form. We will request the name and contact details of a person to contact in case of
      emergency, this information will be recorded and preserved in the subject matter. A period of
      at least three days will be allocated to make the decision whether to participate in the
      study or not. If the participant decides to participate in the study, he will be invited for
      the second visit (oral glucose tolerance test) and on this occasion will sign the consent
      form.

      Visit #2 - Oral glucose tolerance test (OGTT) This test will be performed at Exercise
      Physiology Laboratory at the Department of kinesiology from the University of Montreal under
      the procedure commonly used for these tests. This procedure requires the ingestion of 300 mL
      of water containing 75 g of glucose in the morning (around 8am) after 12 hours of fasting,
      and blood samples and on the tip of a finger at 0, 60 and 120 minutes for the measurement of
      blood glucose. Subjects with higher blood glucose than 5 mmol/L before ingestion of glucose
      and greater than 8 mmol/L after ingestion (60 or 120 min) will not be considered for the
      study. These glucose tolerance standards are more stringent than those of the World Health
      Organization, because the objective of this test is not a diagnosis on glucose tolerance or a
      prognosis of its future development, but just n include in the study subjects who have good
      glucose tolerance.

      Visit #3 - Maximum oxygen uptake testing: cycling VO2max This test will be conducted in the
      Exercise Physiology Laboratory at the Department of kinesiology from the University of
      Montreal. Exercise involves pedaling a stationary bike at a power output (resistance)
      gradually increasing until reaching VO2max. During the execution of the test, the subject is
      wearing surface electrodes to measure heart rate, a mouthpiece and nose clip to measure the
      volume of expired gas as well as the oxygen and carbon dioxide content to determine the
      consumption oxygen and carbon dioxide production. This type of testing is routinely used in
      our laboratory. The test can be stopped at any time by the will of the subject. For this
      test, guidelines established by the Exercise Physiology Laboratory at the Department of
      kinesiology from the University of Montreal will be followed. These guidelines are based on
      recommendations of ethics and safety of the "American College of Sports Medicine".

      4- Experimentation The tests will be conducted at the Exercise Physiology Laboratory at the
      Department of kinesiology from the University of Montreal. The exercise is carried out on
      stationary cycle ergometer. It lasts 120 minutes at a power output corresponding to 60% of
      the VO2max obtained during the maximal test. A volume of a carbohydrate solution (120 g, 6%
      carbohydrate by volume) or sweetened water will be administered to the subject before (571
      mL) and during exercise (286 mL every 30 minutes). The following solutions will be
      administered in a balanced, randomized, double-blind model: maple sap, maple syrup, glucose,
      a commercial sports drink and water with a glucose trace (0.001% carbohydrate by volume).
      Under conditions where only a trace of water or glucose are administered, a natural sweetener
      (stevia) will be added to obtain a sweet taste similar to other conditions. Carbohydrate
      solutions will all be artificially enriched in 13C. The volume ingested after 30 minutes of
      exercise will be artificially enriched in deuterium (D2O, 8g incorporated in the ingestion of
      286 mL).
    

Intervention name(s): Solution ingestion; Constant load cycling; Expired gas sampling; Indirect respiratory calorimetry; Palatability; Gastrointestinal; Blood sampling; Time trial
Intervention type(s): Dietary Supplement; Behavioral; Procedure; Procedure; Other; Other; Procedure; Behavioral
Intervention description(s): Subjects will be required to ingest 2 litres of the experimental solution, spread over the 2 hours of exercise. A first ingestion of 572 mL of solution will be made at rest, 30 minutes before starting exercise, and 286 mL will be ingested immediately before the start of exercise and every 30 minutes during the exercise period.; Subjects will be required to perform 2 hours of cycling exercise at a power output eliciting 60% of VO2max.; Subjects will be asked, twice, to provide a forced expiration into a 10 mL plastic tube in order to collect a sample expired gases. This procedure will be done immediately before blood sampling and ingestion of the solution, every 30 minutes.; A mouthpiece and nose plug will be placed on the subject and expired gases will be analyzed by a metabolic cart during 3 minutes. This procedure will be done immediately before expired gas collection, blood sampling and ingestion of the solution, every 30 minutes.; Subjects will be asked to fill out a short form on the palatability of the solution ingestion, after ingesting the first solution and at the end of exercise, after ingestion the last solution.; At the end of the time trial, subjects will be asked to fill out a short form on gastrointestinal issues they might have had during experimentation.; A catheter will be inserted in an antecubital vein and a saline solution will be continuously perfused to maintain the vessel open. 15 mL of blood will be collected every 30 minutes, immediately before ingesting the solution.; Subjects will be required to complete a simulated 20-km time trial on the cycle ergometer set in linear mode (where resistance is proportional to pedalling cadence), starting at 70% of the peak power output for the cadence spontaneously adopted by the subject during 2 hours of exercise.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: Isotope Labeling, Stable; Exercise, Physical; Calorimetry, Indirect; Athletic Performance; Sugar Maple