Exercise Type That Faster Reduces Postprandial Glycemia.

Study Overview
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Brief Summary
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It is well established that a bout of 50 min of continuous moderate intensity exercise, improves insulin sensitivity up to 48 hours after the bout. However, it is less well known, what is the exercise type more efficient to buffer the elevations in blood glucose elicited by carbohydrate ingestion. The purpose of this study is to elucidate if intervalic exercise is superior to continous on improving postprandial glycemic control.

Detailed Description
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Carbohydrate oxidation, glucose and insulin blood concentrations, isotopically measured rate of appearance of endogenous and exogenous glucose will be measured in 4 ocassions. Participants will undergo in a cross-over randomized fashion the following trials: Exercise pedalling during 50 min at 60% of their VO2max followed by an oral glucose tolerance test (OGTT). Exercise pedalling during 50 min in a hot environment (33ºC) at 60% of their VO2max followed by an oral glucose tolerance test (OGTT). Exercise pedalling during 50 min using intervalic bouts averaging 60% of VO2max followed by an oral glucose tolerance test (OGTT). No exercise, followed by an oral glucose tolerance test (OGTT).

Official Title
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Exercise Type That Faster Reduces Postprandial Glycemia.

Conditions
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Glucose, High Blood, Exercise-Induced Hyperinsulinism

Intervention / Treatment
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* Behavioral: TYPE OF EXERCISE (OR REST)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant must be capable and willing to provide consent, understand, instructions and protocols. Minimal fitness level to be able to complete 50 min of continous exercise at a moderate intensity. Exclusion Criteria: Smokers Pregnancy Any non-controlled medical condition which could influence results or could be worsened by exercise

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Study composed of 4 trials, full-crossover, administered in a randomized order with the inclusion of a control trial.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: AEROBIC EXERCISE<br>50 min of aerobic exercise by pedaling a cycleergometer at 60% of VO2max | Behavioral: TYPE OF EXERCISE (OR REST)<br>* continous exercise in normal temperature, continous exercise in hot environment, intervallic exercise in normal temperature.<br>|
| Placebo Comparator: PLACEBO REST<br>No exercise, resting during 50 min. | Behavioral: TYPE OF EXERCISE (OR REST)<br>* continous exercise in normal temperature, continous exercise in hot environment, intervallic exercise in normal temperature.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood glucose concentration | Incremental area under the curve during the 120 min of the oral glucose tolerance test | 16 weeks | 
| Blood insulin concentration | Incremental area under the curve during the 120 min of the oral glucose tolerance test | 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Carbohydrate oxidation | Measured using indirect calorimetry | 16 weeks | 
| Turnover rate of endogenous and exogenous glucose | Measured using isotopic tracers. | 16 weeks |