Maria, age 48, was recently diagnosed with moderate obstructive sleep apnea. Her clinician recommends a program of caloric restriction and regular aerobic activity in addition to CPAP therapy because:

improved cardiovascular fitness directly cures upper-airway collapse.

lowering body mass reduces soft-tissue pressure around the throat and can lessen airway obstruction.

weight loss eliminates the risk of developing central apneas.

increased daytime activity alone will normalize nocturnal breathing patterns.