Inspiratory Muscle Strength Training in Adults With Obesity

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

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

Study Overview

• Status: Recruiting
• Conditions: Obesity
• Intervention / Treatment: Device: High-resistance inspiratory muscle strength training; Device: Very-low-resistance inspiratory muscle strength training

Detailed Description

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

• Study Type: Interventional
• Enrollment (Estimated): 44
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Joseph C Watso, PhD; Phone Number: 850-644-5260; Email: jwatso@fsu.edu

Study Locations

• United States
  • Florida
    • Tallahassee, Florida, United States, 32306
      • Recruiting
      • Florida State University
      • Contact: Joseph Watso

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: High-resistance inspiratory muscle strength training; 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; 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.
Sham Comparator: Very-low resistance inspiratory muscle strength training; 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; 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.

What is the study measuring?

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

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adherence	The investigators will calculate the percentage of training sessions completed versus prescribed.	Up to 16 weeks
Change in physiological responses during an inspiratory muscle strength training session	The investigators will measure systolic and diastolic blood pressure during an inspiratory muscle strength training session	Up to 16 weeks
Change in blood pressure reactivity during handgrip exercise	Systolic and diastolic blood pressure measured in the laboratory at rest and during a handgrip exercise test.	Up to 16 weeks
Change in the rating of perceived exertion and breathlessness during handgrip exercise	Participants will report their rating of exertion and breathlessness based on two validated scales. Participants will use the written anchors (e.g., light, moderate, heavy) and report the numerical value (e.g., 0-10) associated with their perceived exertion/breathlessness at rest and during an handgrip exercise test.	Up to 16 weeks
Change in muscle sympathetic nerve activity (MSNA) and sympathetic transduction	The investigators will directly record MSNA using an active tungsten microelectrode using standard microneurography techniques. MSNA will be expressed as bursts per minute. Further, the investigators will measure common femoral artery blood flow using ultrasound and mean blood pressure. This will allow determination of sympathetic transduction (the vasoconstrictor and pressor effects of MSNA) expressed as changes in blood pressure (mmHg) or changes in vascular conductance (ml/min/mmHg).	Up to 16 weeks

Collaborators and Investigators

• Sponsor: Florida State University

Study record dates

Study Major Dates

• Study Start (Actual): December 7, 2023
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): July 31, 2027

Study Registration Dates

• First Submitted: July 13, 2022
• First Submitted That Met QC Criteria: July 13, 2022
• First Posted (Actual): July 15, 2022

Study Record Updates

• Last Update Posted (Actual): February 11, 2026
• Last Update Submitted That Met QC Criteria: February 9, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Overweight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity
• Other Study ID Numbers: STUDY00003098; K01HL160772 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data with all HIPAA identifiers removed may be shared in future collaborative efforts pending appropriate data and/or material transfer agreement approvals.
• IPD Sharing Time Frame: One year after completion of trial, indefinitely
• IPD Sharing Access Criteria: A formal plan identifying the intended use of the data and proper completion of appropriate data and/or material transfer agreement approvals with the study PI and their institution.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes