Acute Cardiovascular and Neuromuscular Responses to Walking With Blood Flow Restriction in Older Adults: a Study Protocol for a Randomized Crossover Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Sponsor
- Universidade da Coruña
- Enrollment
- 20
- Locations
- 4
- Primary Endpoint
- RR-Interval Time-Domain Metrics
Study Overview
Brief Summary
The goal of this clinical trial is to explore how walking combined with different levels of partial blood flow restriction (BFR) affects cardiovascular, neuromuscular, and movement (kinematic) variables in older adults.
The main questions it aims to answer are:
Does walking with BFR increase internal effort, as shown by cardiovascular changes, and is this effect proportional to the level of restriction?
Does walking with BFR temporarily reduce neuromuscular control, and is this reduction greater at higher restriction levels?
Does walking with BFR change gait movement patterns?
This study uses a crossover design, meaning that each participant will complete all four conditions and serve as their own control.
Participants will:
Take part in walking sessions under four conditions with different levels of restriction: BFR40%, BFR80%, SHAM (0% BFR), and CON (without BFR).
Have their cardiovascular responses, muscle performance, and gait movement patterns measured.
Report their perceptions of the sessions, including Rate of Perceived Exertion (RPE), satisfaction, and possible side effects.
Detailed Description
This innovative research project aims to explore the effect of the novel BFR technique, combined with walking, as a non-pharmacological strategy to prevent or reverse sarcopenia and thereby improve the quality of life in sedentary older adults. BFR involves the use of a specialized pneumatic cuff to restrict venous blood flow to a muscle while partially inhibiting arterial flow, and it can be applied either at rest or in combination with exercise.
The application of BFR combined with exercise has shown promise as a tool to induce favorable physiological effects at lower training doses, that is, at lower intensities (e.g., lower intensities or slower walking or running speeds), compared to active control groups. However, despite the promising benefits reported in some studies, comprehensive investigation of the cardiovascular and neuromuscular responses during BFR combined with walking remains a largely unexplored area, both in healthy participants and special populations. This knowledge gap is particularly relevant when considering the substantial benefits that older adults and individuals with mobility limitations could gain from BFR combined with walking, especially given their potential difficulty in adhering to the minimum exercise dosage requirements recommended by the World Health Organization
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Treatment
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Masking Description
Participants will be unaware of the condition for each session. One researcher sets the BFR, while a second, blinded researcher supervises and assesses the participant. Data will be analyzed by an external analyst using coded data, keeping session conditions unknown.
Eligibility Criteria
- Ages
- 60 Years to 90 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Aged between 60 and 90 years.
Exclusion Criteria
- •Being institutionalized.
- •Peripheral vascular disease, defined by an ankle-brachial index (ABI) outside the normal range (0.9-1.4).
- •Uncontrolled arterial hypertension (>180/110 mmHg).
- •Any contraindication to exercise, based on self-reported medical history and PAR-Q+.
Outcomes
Primary Outcomes
RR-Interval Time-Domain Metrics
Time Frame: 60 minutes
Standard time-domain HRV metrics-including mean RR intervals (meanRR), the standard deviation of normal-to-normal intervals (SDNN), and the root mean square of successive differences (RMSSD)-will be derived from inter-beat interval data exported from a chest-worn heart rate sensor (epochs of 5 min). Units: milliseconds (ms).
Force steadiness
Time Frame: 10 minutes
Force steadiness will be evaluated from the RMSSD of the coefficient of variation (CV) during a 30-s submaximal isometric knee-extension contraction at 30% MVIC, using a force-gauge device with data-analysis software. Unit: Percentage (%)
Blood pressure
Time Frame: 25 minutes
Systolic, diastolic and mean blood pressure will be obtained by a photoplethysmography sensor. Units: mmHg
Heart rate
Time Frame: 60 minutes
The average and maximum values will be obtained using a chest-worn heart rate sensor. Unit: beats per minute (bpm)
RR-Interval Nonlinear Metric
Time Frame: 60 minutes
Short-term fractal scaling (DFA α1) will be calculated from inter-beat interval data exported from a chest-worn heart rate sensor (epochs of 5 min). Units: dimensionless.
Maximum isometric strength
Time Frame: 10 minutes
Maximum voluntary isometric contraction (MVIC) force during a knee-extension task will be recorded using a force-gauge device. Unit: Newtons (N)
Secondary Outcomes
- Internal subjective load(20 minutes)
- Postural Stability(10 minutes)
- Adverse effects(20 minutes)
- Arterial stiffness(25 minutes)
- Temporal Gait Parameters(20 minutes)
- Temporal Gait Variability(20 minutes)
- Affective Responses(20 minutes)