Effect of lumbar support on human-head movement and discomfort in whole-body vibration

BACKGROUND: It is well known that prolonged sitting can elicit low back pain as a result of the abnormal shape of the spine. This problem becomes worse in whole-body vibration environments where a rocking motion of the pelvis can occur and may amplify the vibration motion transmitted to the lumbar spine. OBJECTIVE: Although the use of lumbar supports is common in static environments, little is known about how the use of such supports changes the biodynamic response and discomfort of the person in whole-body vibration environments. METHODS: The motion at the head and the discomfort of ten participants were recorded under five back-support conditions, including three commercially available lumbar supports. RESULTS:The results indicated significantly lower head motion and discomfort ( p< 0.05) with the use of the lumbar supports than with a simple flat backrest. CONCLUSIONS: All lumbar supports used in this study combined the advantages of reduced head motion and reduced discomfort during whole-body vibration.