Absolutely no! Whole Body Vertical Vibration(WBVV) is the most environmental and the safest exercise. Some people may feel numb, sleepy, dizzy, tired, itchy, sore & stiff shoulders, farts very often and have frequent bowel movement due to personal body constitution after using the vibration machine. The symptoms above are signs to show the improvement of body circulation, the symptoms shall disappear after 1 week. If the symptoms do not disappear, it is best to go for physical examination at the hospital in case of hidden diseases.