Longitudinal Ultrasound Assessment of Diaphragmatic and Respiratory Muscle Function Following Respiratory Muscle Training in Frail Older Adults

NCT07258615 | Active Not Recruiting

• 1 other identifier: UFV-IMT1
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to evaluate the effects of an 8-week inspiratory muscle training program on diaphragmatic and respiratory muscle function in frail older adults aged 80 years and above. Frailty is associated with reduced physical capacity, impaired respiratory performance, and a higher risk of disability. Inspiratory muscle training is a simple, low-cost intervention that may improve breathing function, strength, and overall health in very old adults, but evidence in this age group remains limited. Participants will be randomly assigned to one of two groups: a high-load inspiratory muscle training group or a low-load sham training group. Both groups will use a threshold device and perform 30 breaths once per day, five days per week, for eight weeks. The experimental group will train with progressively increasing resistance (50% to 80% of maximal inspiratory pressure), while the sham group will use a minimal and non-progressive load (15% of maximal inspiratory pressure). All sessions will be supervised and monitored for safety. The main goal of the study is to determine whether inspiratory muscle training improves maximal inspiratory pressure (MIP), an established measure of global inspiratory muscle strength. Secondary outcomes include ultrasound-based assessments of diaphragmatic structure and function, such as diaphragm thickness, contractile fraction, diaphragmatic excursion, inspiratory time, and inspiratory velocity during deep breathing and sniff maneuvers. These measurements will help clarify the physiological adaptations produced by inspiratory muscle training in this population. Assessments will be performed before the intervention, immediately after the 8-week program, and again at one and three months after the end of the intervention to examine both immediate and short-term effects. This study may contribute valuable evidence regarding the safety, feasibility, and clinical benefits of inspiratory muscle training in frail very old adults, supporting its potential implementation in rehabilitation and geriatric care.

Conditions

Frailty Syndrome; Respiratory Muscle Weakness; Age-Related Frailty; Geriatric Health

Keywords

Inspiratory Muscle Training; Diaphragm Ultrasound; Older Adults

Outcome Measures

Primary Outcomes (1)

• Maximal Inspiratory Pressure (MIP)

  Maximal Inspiratory Pressure (MIP) will be measured using a calibrated handheld manometer following standardized respiratory assessment guidelines. Participants will be instructed to perform a maximal inspiratory effort from residual volume through the mouthpiece with their nose occluded. At least three maneuvers will be recorded, ensuring less than 10% variability between attempts. The highest reproducible value (cmH₂O) will be used for analysis. This measure reflects global inspiratory muscle strength and is widely validated in older and frail populations.

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

Secondary Outcomes (9)

• Diaphragm Thickness at End-Expiration (DTE)

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

• Diaphragm Thickness at End-Inspiration (DTi)

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

• Diaphragm Thickening Fraction (DTF)

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

• Diaphragmatic Excursion During Deep Breathing (DMDB)

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

• Inspiratory Time During Deep Breathing (DTDB)

  Before-intervention; Immediately after intervention; 1-month after intervention; 3 months after intervention

Study Arms (2)

Inspiratory Muscle Training

EXPERIMENTAL

Participants perform an 8-week inspiratory muscle training program using a threshold device (PowerBreathe). Training consists of 30 inspirations, once daily, 5 days per week. The initial load is set at 50% of each participant's maximal inspiratory pressure (MIP) and is increased weekly by 5 cmH₂O up to 80% of MIP. All sessions are supervised by healthcare professionals, with continuous monitoring of oxygen saturation and heart rate.

Device: Inspiratory Muscle Training

Inspiratory Muscle Training (Sham)

SHAM COMPARATOR

Participants follow the same 8-week training schedule using the threshold device (PowerBreathe), but with a constant load of 15% of maximal inspiratory pressure (MIP) and no weekly progression. Training consists of 30 inspirations, once daily, 5 days per week. The procedure mimics the experimental intervention but provides minimal physiological stimulus. All sessions are supervised, with monitoring of oxygen saturation and heart rate.

Device: Sham Inspiratory Muscle Training

Interventions

Inspiratory Muscle Training DEVICE

Participants perform 30 breaths once daily, 5 days per week for 8 weeks using a threshold inspiratory muscle training device. The load begins at 50% of maximal inspiratory pressure (MIP) and increases by 5 cmH₂O weekly up to 80% of MIP. Sessions are supervised and oxygen saturation and heart rate are monitored.

Inspiratory Muscle Training

Sham Inspiratory Muscle Training DEVICE

Participants use the same device and schedule as the experimental group (30 breaths once daily, 5 days per week for 8 weeks) but with a constant load of 15% of maximal inspiratory pressure (MIP), with no weekly progression. This mimics the procedure while providing minimal physiological stimulus. Supervision and monitoring are identical to the experimental arm.

Inspiratory Muscle Training (Sham)

Eligibility Criteria

• Age: 80 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)

You may qualify if:

• Adults aged 80 years or older.
• Clinical diagnosis of frailty, defined by a Short Physical Performance Battery (SPPB) score \< 9.
• Ability to stand and walk with or without assistive devices.
• Ability to understand and follow instructions for inspiratory muscle training.
• Stable medical condition for at least 3 months prior to enrollment.
• Capacity to provide informed consent or availability of a legal representative.

You may not qualify if:

• Acute or unstable cardiovascular, respiratory, or metabolic conditions.
• Severe cognitive impairment that prevents understanding the procedures.
• Diagnosis of neuromuscular diseases affecting respiratory muscles (e.g., ALS, myopathies).
• Severe or uncontrolled hypertension (≥180/110 mmHg).
• Recent thoracic or abdominal surgery (\<3 months).
• Severe musculoskeletal disorders limiting participation in training.
• History of recurrent syncope, severe dizziness, or intolerance to respiratory maneuvers.
• Any condition judged by the research team to compromise safety or participation.

Sponsors & Collaborators

• Universidad Francisco de Vitoria: lead

Study Sites (1)

Universidad Francisco de Vitoria

Pozuelo de Alarcón, Madrid, 28223, Spain

Location

MeSH Terms

Conditions

Frailty

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Jorge Sánchez-Infante, PhD, PT

  Universidad Francisco de Vitoria

  PRINCIPAL INVESTIGATOR

Study Design

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

Study Record Dates

• First Submitted: November 20, 2025
• First Posted: December 2, 2025
• Study Start: January 12, 2026
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): July 31, 2026
• Last Updated: February 27, 2026

Record last verified: 2026-02

Locations

ES (1)