This randomized controlled trial aimed to investigate the effects of a 12-week halotherapy intervention on respiratory muscle strength, pulmonary function, aerobic capacity, and intermittent running performance in elite female soccer players. Participants were randomly assigned to either a halotherapy group or a control group. Both groups followed the same preseason soccer training program, while the halotherapy group additionally received regular halotherapy sessions. Pre- and post-intervention assessments included spirometric measurements, respiratory muscle strength, estimated VO₂max, and Yo-Yo Intermittent Recovery Test Level 1 performance.