Effect of Breathing Maneuvers on Peripheral Glucose Metabolism

Study Overview
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Brief Summary
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Two important mechanisms play a major role in the pathogenesis of type 2 diabetes: insulin resistance of the target tissues and the impaired insulin secretion from pancreatic β-cells. Postprandial factors (such as insulin) are perceived by the human brain and induce signals that regulate glucose metabolism via the parasympathetic nervous system. Deep breathing exercise can increase parasympathetic nerve activity. Heart rate variability (HRV) in healthy people can be significantly increased by deep breathing maneuvers, indicating a shift from sympathetic activity to parasympathetic activity. The hypothesis is that this postprandial shift results in a change in peripheral glucose metabolism. In turn, the increased parasympathetic activity could potentially result in a change in postprandial insulin sensitivity or secretion. To test this hypothesis, this study investigates the effect of deep breathing exercise versus normal breathing on insulin sensitivity, on insulin secretion, glucose tolerance, resting energy expenditure, and on parasympathetic tone (analysis of heart rate variability).

Official Title
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Effect of Breathing Maneuvers on Peripheral Glucose Metabolism

Conditions
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Vagus Nerve Stimulation, Insulin Sensitivity, Deep Breathing Maneuver

Intervention / Treatment
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* Other: deep breathing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: HbA1c <6.5% Must be able to understand the explanations of the study and the instructions Exclusion Criteria: Any relevant (according to investigator's judgment) cardiovascular disease Neurological and psychiatric disorders Diabetes mellitus Asthma

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

Sexes Eligible for Study
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Male

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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: deep breathing<br> | Other: deep breathing<br>* Deep breathing maneuver to increase parasympathetic nerve activity<br>|
| No Intervention: normal breathing<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Whole body insulin sensitivity | Insulin sensitivity will be assessed by a 75g OGTT | 0-120 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin secretion | Insulin secretion will be assessed by a 75g OGTT | 0-120 min | 
| Glucose tolerance | Glucose tolerance will be assessed by a 75g OGTT | 0-120 min | 
| Resting energy expenditure | Resting energy expenditure will be assessed by indirect calorimetry | 140-160 min after start of breathing maneuver | 
| Heart rate variability | Heart rate variability will be assessed from continuous ecg recordings | -35 - 120 min |