Abstract

Whole body vibrations are a well known phenomenon in alpine skiing and other sports. Various sport science studies have investigated the vibration load with respect to the corresponding damping behaviour and the consequences of vibrations for sports performance. Other topics of scientific interest are the effects of vibration in strength training. Most of these studies, however, did not pay attention to the safety aspects and dangers and hazard avoidance related to vibration loads. These problems may be manifold and have been mainly studied in work science. From a great number of these studies it is known that whole body vibrations may result in cognitive disorders, vertigo, motion sickness, low back pain with or without degenerative changes in the lumbar spine, visual impairment and others. Moreover, animal studies show, that long-term vibration load may lead to internal bleedings from kidneys, heart, lungs and liver. Therefore the strict rules for minimising vibration input at various workplaces have been elaborated by work science. In sport to date these rules have not been considered at all. Thus this study attempts to assess and quantify the vibration loads which occur in order to estimate possible dangers for the human body. One example of these potential dangers in sports is the reduced visual acuity during whole body vibration. Early studies already showed that vibrations in the resonant frequency range of the head and eyeballs (20-25 Hz) may lead to a reduced visual acuity. The transmission of vibration to the head and the eyeballs mainly depends on factors such as the body posture, joint- and muscle-stiffness and other mechanical properties of the human body. Because of the impostance of an optimal visual acuity in sport-specific situations, an additional lab-study to examine the effects of whole body vibrations on visual performance during vibration-training was carried out. Einleitung (gekürzt)