highly significantp ≤ 0.01
A comparison of CPET-1 to CPET-2 for the total sample revealed numerous highly significant differences ( p ≤ 0.01) albeit with small to moderate effect sizes in ME/CFS at peak effort for Work, Time to level (TTL), V ̇ e, V ̇ O 2 , V ̇ CO 2 , and significant differences ( p ≤ 0.05) in V ̇ T , heart rate (HR), O 2 pulse, DBP, and rate-pressure product (RPP).