Maximal contraction methods influence the magnitude and reliability of global electromyographic signal characteristics

Objective The purpose was two-fold: (1) to examine differences in maximal voluntary isometric torque (MVIT) production, and electromyographic signal amplitude (EMGAMP) and mean power frequency (EMGMPF) values obtained during traditional (MVICTRAD), rapid (MVICRAPID), and ramp (MVICRAMP) maximal voluntary isometric contractions, and (2) to determine if there were differences in the reliability of MVIT, EMGAMP and EMGMPF among the three MVIC types. Approach Twenty-two young males and females completed MVICTRAD, MVICRAPID, and MVICRAMP muscle actions on two separate visits separated by 48 h. During all MVICs, MVIT and EMGAMP and EMGMPF of the vastus lateralis (VL) and rectus femoris (RF) were quantified. Main results MVIT was greater during MVICTRAD and MVICRAPID than during MVITRAMP (both p Significance Investigators may choose MVIC type based on preference or equipment availability. However, investigators should note that MVICRAMP contractions will likely yield the greatest EMGAMP values and more reliable measurements of VL and RF EMGMPF.