Physical activity is a key determinant of physical and mental health among youth; however, participation levels are often influenced by various perceived barriers and facilitators. Understanding these perceptions, together with related psychosocial factors, will provide valuable insights for the development of targeted interventions. This study will aim to investigate perceived barriers and facilitators to physical activity among Turkish youth and to examine their associations with physical activity levels, perceived stress, and daytime sleepiness. This cross-sectional study will include individuals aged 15-24 years. Participants' sociodemographic characteristics will be recorded. Data will be collected using four validated questionnaires administered in a face-to-face setting. Perceived barriers and facilitators to physical activity will be assessed using the Barriers and Facilitators to Youth Physical Activity Questionnaire (BFYPA). Physical activity levels will be evaluated using the short form of the International Physical Activity Questionnaire (IPAQ-SF). Perceived stress levels will be measured using the Perceived Stress Scale (PSS), and daytime sleepiness will be assessed using the Epworth Sleepiness Scale (ESS). Appropriate statistical analyses will be performed to examine relationships between study variables.

Inclusion Criteria:

• Being between 15 and 24 years old
• Being a volunteer

Exclusion Criteria:

• Having a musculoskeletal problem that may alter physical activity habits
• Having a cardiovascular or respiratory problem
• Having diabetes mellitus
• Taking chronic medication
• Having a body mass index of 35 kg/m2 or higher
• Having any other condition that would prevent physical activity

The Physiotherapy and Rehabilitation Application and Research Center of Istinye University