ORIGINAL ARTICLE The effect of exercise on obstructive sleep apnea: a randomized and controlled trial Yesim Salik Sengul & Sevgi Ozalevli & Ibrahim Oztura & Oya Itil & Baris Baklan Received: 17 July 2009 / Accepted: 14 October 2009 / Published online: 7 November 2009 # Springer-Verlag 2009 Abstract Purpose The aim of the study was to assess the effect of breathing and physical exercise on pulmonary functions, apnea-hypopnea index (AHI), and quality of life in patients with obstructive sleep apnea syndrome (OSAS). Methods Twenty patients with mild to moderate OSAS were included in the study either as exercise or control group. The control group did not receive any treatment, whereas the exercise group received exercise training. Exercise program consisting of breathing and aerobic exercises was applied for 1.5 h 3 days weekly for 12 weeks. Two groups were assessed through clinical and laboratory measurements after 12 weeks. In the evaluations, bicycle ergometer test was used for exercise capacity, pulmonary function test, maximal inspiratory-expiratory pressure for pulmonary functions, polysomnography for AHI, sleep parameters, Functional Outcomes of Sleep Questionnaire (FOSQ), Short Form-36 (SF-36) for quality of sleep and health-related quality of health, Epworth Sleepiness Scale for daytime sleepiness, and anthropometric measurements for anthropometric characteristics. Results In the control group, the outcomes prior to and following 12-weeks follow-up period were found to be similar. In the exercise group, no change was found in the anthropometric and respiratory measurements (P >0.05), whereas significant improvements were found in exercise capacity, AHI, and FOSQ and SF-36 (P <0.05). After the follow-up period, it was shown that improvement in the experimental group did not lead to a statistically significant difference between the two groups (P >0.05). Conclusions Exercise appears not to change anthropomet- ric characteristics and respiratory functions while it improves AHI, health-related quality of life, quality of sleep, and exercise capacity in the patients with mild to moderate OSAS. Keywords Mild to moderate obstructive sleep apnea syndrome . Breathing exercise . Physical exercise Introduction Obstructive sleep apnea (OSA) can be described as a condition characterized by repetitive obstruction of the upper airway resulting in oxygen desaturation and awak- ening from sleep, loud snoring, and increased daytime sleepiness [1]. Many studies have shown that a link exists between OSA and cardiovascular disease, chronic heart failure ischemia, hypertension, obesity, and impaired glucose tolerance [2, 3]. A number of factors are likely to play role in development of clinical OSA syndrome (OSAS) ranging from upper airway anatomy to central respiratory control mechanisms. The pathophysiology of OSA is unclear and complex. Several previous studies have explored pulmonary function in the OSAS patients [4, 5]. Interestingly, OSAS has been found to be highly correlated Y. S. Sengul (*) : S. Ozalevli School of Physical Therapy and Rehabilitation, Dokuz Eylul University, Inciralti-Izmir TR-35340, Turkey e-mail: yesim.salik@deu.edu.tr I. Oztura : B. Baklan Departments of Neurology, School of Medicine, Dokuz Eylul University, Izmir, Turkey O. Itil Department of Chest Diseases, Dokuz Eylul University, Izmir, Turkey Sleep Breath (2011) 15:49–56 DOI 10.1007/s11325-009-0311-1