Fig. 3From: Inter-day reliability of surface electromyography recordings of the lumbar part of erector spinae longissimus and trapezius descendens during box liftingMaximum absolute RMS values (RMSmax (mV)) extracted from maximal voluntary contraction of the right and left trapezius and right and left erector spinae extracted from maximal voluntary contraction at week one (x-axis) and week two (y-axis)Back to article page