A Concurrent Cognitive Task Does Not Perturb Quiet Standing in Fibromyalgia and Chronic Fatigue Syndrome

Table 2

The results of repeated-measures ANOVA for each variable.

	Variable	Group  condition	Condition	Group	Post hoc
Area	CoP	F(2, 81) = 0.45	F(1, 81) = 0.76	F(2, 81) = 6.16	HC-CFS, HC-FM
	Postural sway	F(2, 81) = 0.20	F(1, 81) = 4.32	F(2, 81) = 5.08	HC-CFS
	Adjusting ankle torque	F(2, 81) = 2.41	F(1, 81) = 15.93	F(2, 81) = 5.97	HC-FM
Postural sway	Amp-AP	F(2, 81) = 0.84	F(1, 81) = 6.92	F(2, 81) = 4.36	HC-CFS
	Amp-ML	F(2, 81) = 0.41	F(1, 81) = 0.71	F(2, 81) = 4.90	HC-CFS
	F-AP	F(2, 81) = 1.61	F(1, 81) = 13.08	F(2, 81) = 22.08	HC-CFS, HC-FM
	F-ML	F(2, 81) = 1.24	F(1, 81) = 5.67	F(2, 81) = 16.01	HC-CFS, HC-FM
Adjusting ankle torque	Amp-AP	F(2, 81) = 1.07	F(1, 81) = 12.38	F(2, 81) = 4.89	HC-FM
	Amp-ML	F(2, 81) = 0.70	F(1, 81) = 4.79	F(2, 81) = 4.99	HC-CFS, HC-FM
	F-AP	F(2, 81) = 0.82	F(1, 81) = 0.53	F(2, 81) = 2.51	—
	F-ML	F(2, 81) = 0.77	F(1, 81) = 0.01	F(2, 81) = 1.55	—

CoP: center of pressure; Amp: amplitude (mm); F: frequency (Hz); AP: anteroposterior; ML: mediolateral; conditions: baseline and experimental conditions with the concurrent cognitive task; HC: healthy control; CFS: chronic fatigue syndrome; FM: fibromyalgia; ; .