EMG—Surface EMG data from trunk, gluteal, and thigh muscles were acquired using a 16-
channel recording system (Myomonitor III, Delsys Inc., Boston, MA) with preamplified
silver-silver chloride, single differential, parallel bar surface electrodes that were 1.0 cm in
length with a 1.0 cm interelectrode distance. The system had an input impedance of
>1015Ω // 0.2pF, a common mode rejection ratio of −92 dB, signal-to-noise ratio of 1.5 μV,
and a pre-amplifier gain 1000 V/V ±1%. EMG data were collected at 1200 Hz, preamplified
with a gain of 10, and filtered with a high pass filter of 20 Hz and low pass filter of 450 Hz.