Effects of Exercise Training on Osa and Sleep Quality

1631 Exercise Training and OSA Severity—Kline et al preliminary evidence. Epidemiologic research has suggested that individuals who are physically active have a reduced risk of OSA compared to individuals who are less active.10,11 Moreover, small-scale (often uncontrolled) experimental studies have found the apnea-hypopnea index (AHI) to be reduced up to 50% following chronic exercise training.12-15 Although weight loss is the most obvious plausible mediator explaining how exercise may reduce OSA severity, decreases in AHI following exercise training have been found to be independent of changes in body weight in the limited epidemiologic and experimental studies that have examined this hypothesis.10,12,13 Other possible mechanisms of improvement in OSA following exercise training include a general strengthening and fatigue resistance of the ventilatory and upper airway dilator muscles,16 attenuation of respiratory instability from reduced sleep fragmentation,17 decreased nasal resistance,18 and prevention of lower-extremity fluid accumulation.19 Regardless of whether OSA severity is improved, exercise training may improve sleep in this population. There is a consistent epidemiologic association between exercise and sleep quality,20 and experimental studies utilizing individuals without OSA have found that chronic exercise training significantly improves sleep.21 However, experimental research in individuals with OSA has produced conflicting results about changes in objective sleep from exercise training,12-15 and subjective sleep quality has not been evaluated. INTRODUCTION Obstructive sleep apnea (OSA) is a prevalent sleep disorder, affecting up to 15% of the population.1 If left untreated, OSA has potentially severe health consequences, such as cognitive impairment,2 cardiovascular disease,3 diabetes,4 and early mortality.5 Unfortunately, treatment options for OSA remain limited. Although continuous positive airway pressure (CPAP) is effective when used,6 much of its benefits go unrealized in practice because of low adherence.7 Other treatment options, such as oral appliances and upper airway surgery, only partially reduce OSA severity and produce frequent side effects.8,9 In addition, the effects of these treatments on the health consequences of OSA are not well established.8,9 The possible utility of exercise training in the management of OSA has not been thoroughly investigated despite intriguing EFFECTS OF EXERCISE TRAINING ON OSA AND SLEEP QUALITY