Table 1. Root mean square of the fundamental and the harmonics for the surface electromyography of several lower limb muscles during whole-body vibration, without load and with an additional load of 33 kg (95% CI). Fundamental (mV) Harmonics (mV) Vastus Lateralis No load 0.042 - 0.086 0.021 - 0.049 With load 0.045 - 0.115* 0.030 - 0.076** Rectus Femoris No load 0.019 - 0.033 0.014 - 0.019 With load 0.029 - 0.047*** 0.019 - 0.027*** Biceps Femoris No load 0.010 - 0.016 0.005 - 0.009 With load 0.013 - 0.024** 0.008 - 0.013*** Soleus No load 0.006 - 0.011 0.006 - 0.014 With load 0.011 - 0.025*** 0.013 - 0.034*** Gastrocnemius Lateralis No load 0.003 - 0.005 0.002 - 0.004 With load 0.005 - 0.010** 0.006 - 0.012*** With load > no load (*p < 0.05, **p < 0.01, ***p < 0.001)