Participants classified as having low functional capacity according to the predefined functional capacity assessment criteria will undergo evaluation of balance performance, respiratory muscle strength, pulmonary function, vital signs, and core endurance in a single-session assessment.

Participants classified as having moderate functional capacity according to the predefined functional capacity assessment criteria will undergo evaluation of balance performance, respiratory muscle strength, pulmonary function, vital signs, and core endurance in a single-session assessment.

Participants classified as having high functional capacity according to the predefined functional capacity assessment criteria will undergo evaluation of balance performance, respiratory muscle strength, pulmonary function, vital signs, and core endurance in a single-session assessment.

This observational study evaluates the relationship between respiratory muscle strength and balance in healthy individuals using spirometry, MIP/MEP, core endurance tests, and the Y Balance Test.

Measured using the Y-Balance Test (anterior, posteromedial, posterolateral directions) Y Balance Test It is a simple and effective test used to evaluate dynamic balance. The participant is asked to stand on one leg and reach as far as possible in three directions (anterior, posterolateral, and posteromedial) with the non-stance leg. The test is performed in the following order: anterior right, anterior left, posteromedial right, posteromedial left, posterolateral right, and posterolateral left.

Maximum inspiratory pressure (MIP) is a measure of the strength of the inspiratory muscles and represents the negative pressure generated when an individual inhales as forcefully as possible after a full exhalation.

Measures the strength of expiratory muscles and is the positive pressure generated during forceful exhalation after a deep breath. It is assessed using a mouth pressure meter (MPM) in a seated position with a nose clip, taking the best of at least three trials.

The plank test evaluates the endurance of deep core muscles (transversus abdominis, multifidus); the individual maintains a prone position supported on the elbows and toes, keeping the body in a straight line, and the duration the position can be held is recorded.