EMG activities were collected with a sampling rate of 1500 Hz
by use of the TeleMyo DTS Telemetry system (Noraxon Inc.,
Scottsdale, AZ, USA). EMG activities and kinematic data
obtained from the electromagnetic sensor were synchronized with
a manual trigger. Four muscles (UT, MT, LT, and SA) that play
key roles in scapular control were chosen for analysis. After the
electrode sites were shaved and cleaned with scrubbing gel and
alcohol, electrodes with 2-cm center-to-center interelectrode distance
were applied to the skin overlying each muscle of the
dominant arm according to the SENIAM recommendations15 and
a previous study. We chose these 4 muscles because these muscles
are involved in scapular control