NCT07427121

Brief Summary

The goal of this research study is to evaluate the effects of a single session of rehabilitation in healthy adults, before noninvasive mechanical ventilation (MV). MV can help support breathing function during sleep or illness. High levels of MV support have been reported to alter the function of the diaphragm muscle, the primary breathing muscle, in people with compromised health. However, rehabilitation may have some potential to improve diaphragm function in advance of using MV. This study will test different rehabilitation interventions, including (1) inspiratory strength training (IST), (2) transcutaneous spinal cord stimulation (TSCS), or sham TSCS. Before and after MV, participants will complete breathing strength tests and responses to phrenic nerve stimulation.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
16

participants targeted

Target at below P25 for not_applicable

Timeline
17mo left

Started Mar 2026

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress20%
Mar 2026Dec 2027

First Submitted

Initial submission to the registry

February 17, 2026

Completed
6 days until next milestone

First Posted

Study publicly available on registry

February 23, 2026

Completed
1 month until next milestone

Study Start

First participant enrolled

March 30, 2026

Completed
1 year until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 31, 2027

Expected
9 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2027

Last Updated

May 5, 2026

Status Verified

April 1, 2026

Enrollment Period

1 year

First QC Date

February 17, 2026

Last Update Submit

April 29, 2026

Conditions

Inspiratory Strength Training (IST)Transcutaneous Spinal StimulationSham Spinal Stimulation

Keywords

diaphragmphrenic nervemaximal inspiratory pressuremechanical ventilation

Outcome Measures

Primary Outcomes (2)

  • Maximal inspiratory pressure

    The most negative pressure generated during a maximal inspiratory effort.

    T1: baseline strength, T2: 2 hours after MV, T3: 24 hours after MV

  • Phrenic CMAP Response

    EMG response to supra maximal and bilateral phrenic stimulation

    up to 24 hours

Secondary Outcomes (1)

  • Diaphragm thickness and excursion

    up to 24 hours

Other Outcomes (1)

  • Two-minute step test (2M-ST)

    Two hours and twenty-four hours post-MV.

Study Arms (3)

Sham Stimulation

SHAM COMPARATOR

Transcutaneous spinal cord stimulation at reduced intensity, lasting 1 minute at the beginning and end of a 20-minute session.

Other: Sham Stimulation

Spinal cord stimulation

ACTIVE COMPARATOR

Transcutaneous spinal cord stimulation at 2mA intensity, for 20 minutes.

Device: Spinal cord stimulation

Inspiratory strength training

EXPERIMENTAL

5 sets of 5 breaths of high-intensity inspiratory strength training

Behavioral: Inspiratory Strength Training

Interventions

Spinal cord stimulationDEVICE

Transcutaneous spinal cord stimulation at 2mA intensity, for 20 minutes.

Spinal cord stimulation
Inspiratory Strength TrainingBEHAVIORAL

5 sets of 5 breaths of high-intensity inspiratory strength training

Inspiratory strength training
Sham StimulationOTHER

Transcutaneous spinal cord stimulation at reduced intensity, lasting 1 minute at the beginning and end of a 20-minute session.

Sham Stimulation

Eligibility Criteria

Age25 Years - 80 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Non-smokers Sedentary or recreationally active Normal lung function No history of claustrophobia

You may not qualify if:

  • Current smoking or vaping Obstructive lung disease Use of antibiotics or systemic corticosteroids to treat an acute condition History of sepsis or metastatic disease Post infectious conditions that affect breathing Diagnosed with a neurological or neuromuscular condition Any use of supplemental oxygen, continuous positive airway pressure (CPAP), or other positive pressure ventilation to treat sleep apnea Cardiac disease Orthopedic conditions that impair lung expansion Pregnancy Implanted metallic devices within 10 cm of the cervical spine

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Florida

Gainesville, Florida, 32610, United States

RECRUITING

Related Publications (7)

  • Ando R, Ohya T, Kusanagi K, Koizumi J, Ohnuma H, Katayama K, Suzuki Y. Effect of inspiratory resistive training on diaphragm shear modulus and accessory inspiratory muscle activation. Appl Physiol Nutr Metab. 2020 Aug;45(8):851-856. doi: 10.1139/apnm-2019-0906. Epub 2020 Feb 12.

    PMID: 32049562BACKGROUND

  • Laghi F, Shaikh H, Littleton SW, Morales D, Jubran A, Tobin MJ. Inhibition of central activation of the diaphragm: a mechanism of weaning failure. J Appl Physiol (1985). 2020 Aug 1;129(2):366-376. doi: 10.1152/japplphysiol.00856.2019. Epub 2020 Jul 16.

    PMID: 32673161BACKGROUND

  • Nierat MC, Similowski T, Lamy JC. Does trans-spinal direct current stimulation alter phrenic motoneurons and respiratory neuromechanical outputs in humans? A double-blind, sham-controlled, randomized, crossover study. J Neurosci. 2014 Oct 22;34(43):14420-9. doi: 10.1523/JNEUROSCI.1288-14.2014.

    PMID: 25339753BACKGROUND

  • Locher C, Raux M, Fiamma MN, Morelot-Panzini C, Zelter M, Derenne JP, Similowski T, Straus C. Inspiratory resistances facilitate the diaphragm response to transcranial stimulation in humans. BMC Physiol. 2006 Jul 29;6:7. doi: 10.1186/1472-6793-6-7.

    PMID: 16875504BACKGROUND

  • Hawkes EZ, Nowicky AV, McConnell AK. Diaphragm and intercostal surface EMG and muscle performance after acute inspiratory muscle loading. Respir Physiol Neurobiol. 2007 Mar 15;155(3):213-9. doi: 10.1016/j.resp.2006.06.002. Epub 2006 Jul 18.

    PMID: 16846758BACKGROUND

  • Fauroux B, Isabey D, Desmarais G, Brochard L, Harf A, Lofaso F. Nonchemical influence of inspiratory pressure support on inspiratory activity in humans. J Appl Physiol (1985). 1998 Dec;85(6):2169-75. doi: 10.1152/jappl.1998.85.6.2169.

    PMID: 9843540BACKGROUND

  • Bresciani G, Beaver T, Martin AD, van der Pijl R, Mankowski R, Leeuwenburgh C, Ottenheijm CAC, Martin T, Arnaoutakis G, Ahmed S, Mariani VM, Xue W, Smith BK, Ferreira LF. Intraoperative phrenic nerve stimulation to prevent diaphragm fiber weakness during thoracic surgery. PLoS One. 2025 Apr 1;20(4):e0320936. doi: 10.1371/journal.pone.0320936. eCollection 2025.

    PMID: 40168300BACKGROUND

MeSH Terms

Interventions

Spinal Cord Stimulation

Intervention Hierarchy (Ancestors)

Electric Stimulation TherapyTherapeuticsPhysical Therapy ModalitiesRehabilitation

Study Officials

  • Barbara K Smith, PhD

    University of Florida

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Barbara K Smith, PhD, PT

CONTACT

352-294-5315bksmith@ufl.edu

Ushna Khan, MD

CONTACT

352-273-6855ushnakhan@ufl.edu

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 17, 2026

First Posted

February 23, 2026

Study Start

March 30, 2026

Primary Completion (Estimated)

March 31, 2027

Study Completion (Estimated)

December 31, 2027

Last Updated

May 5, 2026

Record last verified: 2026-04

Data Sharing

IPD Sharing
Will share

Participant data that underlie the results reported in this article after deidentification.

Shared Documents
STUDY PROTOCOL
Time Frame
9 months and ending 36 months following article publication.
Access Criteria
Investigators whose proposed use of the data has been approved by an independent review committee.

Locations

US(1)