Feasibility and Effects of Inspiratory Muscle Training Combined With Blood Flow Restriction for Frail Older Adults

Feasibility and Effects of Inspiratory Muscle Training Combined With Blood Flow Restriction for Frail Older Adults: A Pilot Randomized Controlled Trial

This randomized controlled trial study aims to evaluate the feasibility and preliminary efficacy of a combined inspiratory muscle training (IMT) and blood flow restriction (BFR) intervention in frail older adults. Outcomes of interest include feasibility, physical function, respiratory muscle strength, handgrip strength, five-times sit-to-stand performance, body composition, frailty level, fall efficacy, blood pressure, and adverse events.

This is a parallel randomized controlled trial. 30 participants who are older adults with frailty will be enrolled.

Eligible participants who complete the baseline measurements will be randomly allocated to a combined BFR and IMT intervention group (N=15) or in the control group with BFR and sham IMT (N=15).

Primary outcomes include feasibility and physical function (i.e., the Short Physical Performance Battery (SPPB), 6-minute walk test (6MWT), and Time Up and Go (TUG) test). Secondary outcomes include respiratory muscle strength, handgrip strength, five-times sit-to-stand performance, body composition, frailty level, fall efficacy, blood pressure, and adverse events. All outcomes will be assessed at baseline (T0) and immediately after the 6-week intervention period (T1) in both groups.

Inclusion Criteria:

• Community-dwelling adults aged 65 years and older who are classified as at least "vulnerable" using the Clinical Frailty Scale (score ≥4).
• Participants must have no cognitive impairment and be able to follow commands, as assessed by the Mini-Mental State Examination (MMSE).

Exclusion Criteria:

• (1) are unable to participate in exercise (e.g., due to severe musculoskeletal disorders)
• (2) have high-risk factors for exercise, such as uncontrolled hypertension (>150 mmHg systolic blood pressure (SBP) / >90 mmHg diastolic blood pressure (DBP), coagulation disorders, and deep venous thrombosis
• (3) have hematological disorders or are using hematology related-medications
• (4) have significant comorbidities, including a history of stroke, diabetes with severe complications, or cardiovascular diseases
• (5) chronic lung conditions (e.g., obstructive pulmonary disease, asthma), and
• (6) have participated in a structured exercise training program within the past 3 months at a frequency exceeding three sessions per week.