Table 2b Calculated with different thresholds in VM muscle. NS, were not calculated because of non significant correlation between actual and estimated number of bursts. Threshold Value 25 % (n=9) 35 % (n=9) 45 % (n=9) 2 NS NS NS 3 NS NS NS 4 NS 7.3 NS 5 NS NS NS 6 NS 5.0 NS 7 NS 3.9 NS 8 NS 6.1 NS 9 NS 3.4 NS 10 NS 5.1 NS 11 3.0 1.6 NS