Table 1 Median frequency and duration of differential activation in fibromyalgia (FM) and healthy controls (CON); mean values ± 1 standard deviation (SD) and minimum and maximum values.

Frequency ( s ^-1 )

0 kg

0.43 ± 0.08

0.24-0.56

0.37 ± 0.11

0.14-0.53

0.028*

1 kg

0.42 ± 0.10

0.23-0.57

0.35 ± 0.12

0.12-0.60

0.033*

2 kg

0.37 ± 0.11

0.11-0.51

0.34 ± 0.12

0.14-0.53

0.303

4 kg

0.39 ± 0.11

0.14-0.56

0.36 ± 0.12

0.14-0.60

0.280

Duration (sec)

0 kg

1.21 ± 0.26

0.89-2.08

1.51 ± 0.61

0.95-3.59

0.022*

1 kg

1.28 ± 0.36

0.88-2.23

1.67 ± 0.85

0.82-4.30

0.025*

2 kg

1.57 ± 0.83

0.98-4.60

1.71 ± 0.73

0.95-3.59

0.500

4 kg

1.42 ± 0.59

0.90-3.59

1.59 ± 0.68

0.84-3.58

0.325