Effects of Respiratory Muscle Exercises on Glucose Tolerance in Healthy Adults

Study Overview
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Brief Summary
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To evaluate the acute effects of respiratory muscle exercises vs. a control intervention on blood glucose kinetics in healthy adults after an oral glucose tolerance test.

Official Title
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Effects of Respiratory Muscle Exercises on Glucose Tolerance in Healthy Adults

Conditions
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Healthy Aging, Healthy Diet

Intervention / Treatment
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* Other: 5min respiratory muscle exercises
* Other: 15min respiratory muscle exercises


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥18 years Healthy Non-smoking Body mass index (BMI): 18.5 - 29.9 kg∙m-2 Normal lung function Willing to adhere to study rules Exclusion Criteria: Known or suspected non-compliance, drug or alcohol abuse Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant Previous enrolment into the current study Intake of medications affecting metabolism, the cardiovascular or the respiratory system, or sleep Acute illness or chronic conditions of the gastrointestinal tract, and health conditions affecting metabolism, the cardiovascular or the respiratory system, or sleep Pregnancy, breastfeeding, or intention to become pregnant during the study

Ages Eligible for Study
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Minimum Age: 18 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: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: This study consists of four visits to the laboratory, each separated by at least 24 hours and each lasting approximately 2.5h. Total duration for each participant is approximately 2 weeks. The study is conducted in 40 healthy adults (≥ 18 years). The study is a randomized, controlled cross-over trial. We chose a cross-over design in order to test the effects of different respiratory exercises compared to a control intervention in order to minimize variability since each subject serves as his/her own control. Due to the nature of the intervention (respiratory muscle exercises), it is not possible to blind participants to the interventions.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Respiratory Muscle Exercises<br>Two respiratory muscle exercises | Other: 5min respiratory muscle exercises<br>* 5 min of hyperpnea at a target intensity of 60-80% MVV 15-30min after ingestion of 75g of glucose<br>Other: 15min respiratory muscle exercises<br>* 5 min of hyperpnea at a target intensity of 60-70% MVV 15-30min after ingestion of 75g of glucose<br>|
| No Intervention: Control<br>The control intervention consists of quiet sitting for 15 min | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak blood glucose concentration | Peak blood glucose concentration will be determined in the three conditions (5min or 15min respiratory muscle exercises or control). | throughout the study, an expected average of 2 weeks per participant | 
| area under the glucose-time curve | Area under the glucose-time curve will be determined in the three conditions (5min or 15min respiratory muscle exercises or control). | throughout the study, an expected average of 2 weeks per participant |