1. Introduction. Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic complex disease characterized by unrelenting fatigue, post-exertional malaise, sleep problems, cognitive impairment, and orthostatic intolerance [].This debilitating illness is known to affect between 836,000 and 2.5 million people in the United States alone [1,2,3], and the majority of the patients ....