Inspiratory Muscle Strength Training in Adults With Obesity

Study Overview
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Brief Summary
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The purpose of this study is to determine whether inspiratory muscle strength training reduces blood pressure in adults with obesity.

Detailed Description
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Obesity affects four-in-ten American adults and is associated with hypertension and greater all-cause mortality. Irrespective of weight loss, aerobic exercise reduces arterial blood pressure (BP) and improves cardiometabolic health. However, nearly half of adults with obesity do not perform aerobic exercise because of low leisure time availability and exertional dyspnea secondary to high chest wall mass-related inspiratory muscle dysfunction. In other clinical populations, emerging data demonstrates time-efficient high-resistance inspiratory muscle strength training (IMST) reduces BP and improves respiratory muscle function. Therefore, the investigators will determine whether eight weeks of daily high-resistance IMST reduces BP, improves respiratory muscle function, and concomitantly reduces exertional dyspnea in a randomized, double-blinded, sham-controlled (i.e., very low-resistance IMST) clinical trial among adults with obesity

Official Title
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Time-Efficient Inspiratory Muscle Strength Training as a New Approach to Lower Blood Pressure, Improve Respiratory Function, and Reduce Exertional Dyspnea in Adults With Obesity

Conditions
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Obesity

Intervention / Treatment
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* Device: High-resistance inspiratory muscle strength training
* Device: Very-low-resistance inspiratory muscle strength training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Body mass index 30 - 40 kg/m2 Exclusion Criteria: Not weight stable (<5% change in body mass over the past six months) Overt cardiovascular, neurological, renal, liver, and/or metabolic illness (e.g., diabetes mellitus) Current, or history of uncontrolled, Stage 2 hypertension (blood pressure >140 / 90 mmHg; anti-hypertensive medications are permitted) Diagnosed obstructive sleep apnea Previous bariatric surgery Diagnosis or signs (e.g., values below the lower limit of normal) of overt airway disease(s) Current or recent (regular use within the past 6 months) use of tobacco or nicotine products (e.g., cigarettes, vaping) Pregnant (self-reported and confirmed via urine pregnancy test), lactating (self-reported), or post-menopausal (self-reported) females Prisoners Per the POWERbreathe® company: Patients who have undergone recent abdominal surgery and those with abdominal hernia. Asthma patients who have a very low symptom perception and suffer from frequent, severe exacerbations or with an abnormally low perception of dyspnea. If a patient is suffering from a ruptured eardrum or any other condition of the ear. Patients with marked elevated left ventricular end-diastolic volume and pressure. Patients with worsening heart failure signs and symptoms after training. If an individual is suffering from a cold, sinusitis or respiratory tract infection, it is advised that they do not use the POWERbreathe device.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 45 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: High-resistance inspiratory muscle strength training<br>Participants will perform high-resistance inspiratory muscle strength training on a daily basis for eight weeks using a handheld device that produces resistance that increases the effort of breathing in. | Device: High-resistance inspiratory muscle strength training<br>* Participants will perform high-resistance inspiratory muscle strength training on a daily basis for eight weeks using a handheld device that produces resistance that increases the effort of breathing in.<br>|
| Sham Comparator: Very-low resistance inspiratory muscle strength training<br>Participants will perform very-low-resistance inspiratory muscle strength training on a daily basis for eight weeks using a handheld device that produces resistance that increases the effort of breathing in. | Device: Very-low-resistance inspiratory muscle strength training<br>* Participants will perform very-low-resistance inspiratory muscle strength training on a daily basis for eight weeks using a handheld device that produces resistance that increases the effort of breathing in.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in laboratory-measured blood pressure | Systolic and diastolic blood pressure measured in the laboratory | Up to 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in ambulatory blood pressure | Systolic and diastolic blood pressure measured at home using an automated monitor | Up to 16 weeks | 
| Change in inspiratory muscle strength | Peak inspiratory pressure measured in the laboratory | Up to 16 weeks | 
| Change in blood pressure reactivity during aerobic exercise | Systolic and diastolic blood pressure measured in the laboratory at rest and during an incremental aerobic exercise test | Up to 16 weeks | 
| Blood pressure during respiratory muscle testing | Systolic and diastolic blood pressure measured in the laboratory at rest and during a respiratory muscle exercise test (eucapnic voluntary hyperpnea) | Up to 16 weeks |