Respiratory muscle weakness significantly limits functional capacity in various populations, yet conventional respiratory muscle training (RMT) often requires coached, mouthpiece-based maneuvers that may be limited by technique and adherence. This proof-of-concept study evaluated the physiological efficacy of a novel, low-cost wearable resistance vest designed to provide continuous circumferential thoracic loading during spontaneous breathing to improve respiratory muscle strength in healthy adult males.

Respiratory muscle weakness contributes to impaired ventilation and reduced functional capacity across a wide range of respiratory, neuromuscular, and critical care conditions. Conventional respiratory muscle training (RMT) typically relies on mouthpiece-based threshold or resistive devices that require repeated volitional breathing maneuvers, appropriate technique, and sustained patient adherence. These requirements may limit their applicability in some patient populations.

This study evaluated a custom-designed wearable resistance vest developed to provide continuous circumferential thoraco-abdominal loading during spontaneous breathing. Unlike conventional RMT devices that apply resistance only during specific inspiratory or expiratory maneuvers, the wearable vest delivers a sustained external mechanical load throughout normal daily breathing. The intervention was designed to increase the work of breathing during routine activities while allowing participants to breathe naturally without performing prescribed respiratory exercises.

The study was conducted as a prospective, single-group, repeated-measures proof-of-concept investigation to determine the physiological effects of this wearable device in healthy adult males. Participants wore the individually calibrated vest during normal daily activities over a three-week intervention period with progressively increasing daily wear times. Respiratory muscle strength was assessed at baseline and weekly throughout the intervention using standardized measurements of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP).

The primary objective was to determine whether progressive circumferential thoracic loading could improve respiratory muscle strength. A secondary objective was to evaluate the physiological feasibility and tolerability of this wearable approach as a potential alternative to conventional device-based respiratory muscle training.

As a proof-of-concept study conducted in healthy volunteers, the findings are intended to establish preliminary physiological evidence and to inform the design of future controlled clinical studies evaluating this wearable technology in patient populations with respiratory muscle weakness or impaired ventilatory function.

Inclusion Criteria:

Healthy adult males Age 18 years and older Non-smokers Free from known cardiovascular diseases Free from known respiratory diseases Free from known neuromuscular diseases Able to provide written informed consent

Exclusion Criteria:

Current smokers or history of smoking within the last 6 months Known history of chronic pulmonary disease (e.g., asthma, COPD) Known cardiovascular or neuromuscular disorders Musculoskeletal conditions preventing the comfortable use of the vest Inability to complete the three-week training protocol

Male and those participant were recruited from a university setting via convenience sampling.