Table 1.

Description of all parameters used to simulate the surface representation of action potentials generated in pennate fibres

Parameter	Value
Pennation angle	30 deg
Skin thickness	1 mm
Subcutaneous tissue thickness	2 mm
Fibre length	Gaussian distribution with 50 mm mean and 2 mm s.d.
Location of end-plates	Gaussian distribution with the mean corresponding to fibre centre and 1 mm s.d.
Fibre density (surface)	40 fibre mm−1
Number of motor units	300
Skin conductivity	4.3 × 10−4 S m−1
Fat conductivity	4.0 × 10−2 S m−1
Muscle longitudinal conductivity	40 × 10−2 S m−1
Muscle axial conductivity	9.0 × 10−2 S m−1
Conduction velocity (CV)	Gaussian distribution with 4 m s−1 mean and 0.3 m s−1s.d.

The model we used is an extension of that proposed by Mesin & Farina (2004), to further include the adipose and the skin layers separating the muscle tissue from the recording electrodes.