However, when performing the
bench press at 80 % of 1RM, pectoralis major EMG
amplitude is almost maximal (at 93 % of MVIC), which suggests that loads of 80 % of 1RM are sufficient to train the pectoralis major
during the
bench press.
In fact, clavicular head EMG
amplitude is higher when using a narrow grip than when using a wide grip
during decline, flat and incline
bench presses (Barnet et al. 1995).