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 1,5 hours for experimentation (warmup, and 6 X 3-minutes intermittent efforts at 95% of MAP on a stationary bicycle with ingestion of a solution carbohydrates or sweetened water).

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".

Visit #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. Prior to exercise, electrodes (EMG) will be installed on the subject's hands, optodes helmet (NIRS) will be installed on the subject's head, and a first dose (167 mL) of a solution of carbohydrates, (120 g, 6% carbohydrate by volume), sweetened or unsweetened water will be administrated to the subject. During exercise protocol, the following solutions will be administered to the subject in a balanced, randomized, double-blind model: maple sap, maple syrup, glucose, a commercial sports drink and water. He will then begin a standardized warmup consisting of 10 minutes cycling at 40% of MAP followed by 6 bouts of 10 seconds at 95% of MAP separated by 50 seconds of passive recovery. After the second dose of solution (167 mL), the subject will have to do 6 efforts of 3 minutes at 95% of MAP, each bout separated by 3 minutes of passive recovery. He will be administered an additional dose after the first 4 efforts (4 X 167 mL). After the last effort, one last dose (167 mL) will be administered, and the subject will be asked to stay in the laboratory for the 45 minutes following the last effort. Cognitive task as well as blood sugar level will be evaluated before the exercise protocol, during the 3-minutes exercise bouts, and every 15 minutes during the 45 minutes following exercise. Heart rate, brain oxidation and muscle electrical activity will be measured continuously during recovery. The total duration of this visit is approximately 90 minutes.