Obstructive sleep apnea (OSA) is a clinical condition characterized by the repetitive obstruction of the upper airway during sleep, resulting in nocturnal hypoxaemia and fragmented sleep. Fragmented sleep leads to daytime sleepiness that causes alterations in reaction times and reflexes . Postural stability is an important function of the human body. It is shown that the sleep deprivation disturbs daytime postural stability and balance. Aim of this study is to examine the influence of OSA severity and daytime sleepiness on postural stability, balance and fall risk.

Inclusion Criteria:

• Subjects with recent diagnosis of OSA (AHI≥5)
• BMI of ≤35 kg/m2
• Being sedentary

Exclusion Criteria:

• Having OSA treatments (CPAP, oral devices, nasal surgery, tennis ball/positional therapy, diuretic),
• Having a disease that can affect balance (vestibular, neurological, orthopedic ...) performing regular exercise
• Morphological defect (facial malformation, etc.) which may cause sleep disorders
• Uncontrolled hypertension or arrhythmia
• History of smoking or alcoholism
• Orthopedic, neurological or musculoskeletal problems which impede exercising
• Pregnancy
• Uncompensated clinical conditions such as chronic obstructive pulmonary disease, interstitial lung disease, heart failure, or rheumatic and psychiatric diseases

Subjects aged between 30-65 years who are recently diagnosed with mild, moderate or severe OSA (AHI≥5) and not receiving any treatment yet will be included in the study.