Validity and Reliability of a Mixed Reality-Based 6-Minute Walk Test

Inclusion Criteria: * Aged between 18 and 65 years, * Asymptomatic, with no known or active cardiopulmonary, neurological, or musculoskeletal disease-related symptoms, * Ability to ambulate independently without the use of an assistive device, * Visual, auditory, and vestibular functions sufficient to tolerate mixed reality applications, * Cognitive ability sufficient to understand and follow test instructions, * Ability to read, understand, and follow instructions in Turkish, * Willingness to participate voluntarily in the study and provision of written informed consent. Exclusion Criteria: * Inability to safely complete walking tests due to serious musculoskeletal conditions (e.g., recent fracture, severe arthritis, advanced osteoarthritis, significant muscle or tendon injury), * Presence of severe cardiopulmonary disease or any medical condition that may pose a risk during exercise testing (e.g., uncontrolled hypertension, heart failure, severe arrhythmia history, chronic obstructive pulmonary disease), * High risk of balance loss or spatial disorientation in the mixed reality environment due to vestibular, visual, or auditory impairments, * History of epilepsy or neurological conditions contraindicating mixed reality or head-mounted device use, * Severe migraine, significant motion sickness history, or high risk of dizziness/nausea during mixed reality applications, * Cognitive impairment or severe psychiatric conditions preventing understanding or completion of test procedures, * Insufficient motivation or cooperation that may interfere with safe participation in the study.