Investigation On The Affect Of Seat Heights On The Ground Reaction Forces And Body Postures During The Sit-to-walk Movement

Sit-to-walk is a routine daily life activity, moving from sitting to walking the subject body shows the ordered position changes. It involves all age groups but infants and is more difficult than walking. It may lead to fall, fracture and other complication especially for the weak lower limb functions and vision loss elderly. DLUT4060piezoelectric multi-component force platforms and DVM8820three-dimensional infrared image capture system were used to test the sit-to-walk movements of11healthy retired elderly (72.6+-2.2years old) and9healthy college younger (19.7+-1.3years old) subjects came from Dalian University of Technology. Aiming for explore the different movement strategies and the risk of fall by the two age groups. By sports biomechanics and statistical analysis, the results showed that:1. Combined through the sports biomechanics analysis and subjects self-select the best seat height of the statistical results found that the best seat height was100%SH of the two age groups. It could apply the biggest advantage on the biomechanics, the most comfortable, the maximum safety, and the lowest risk of fall.2. For the two age groups, lower and higher seat height would affect the subjects’ actions and the lower-limb function; especially for the elderly, the lower seat height, the greater negative impact.3. The elderly should not finish the sit-to-walk quickly and smoothly like the younger. And the sit-to-walk movement was a threat to the elderly’body balance and stability control system, easily lead to falls.So the popliteal fossa height must be concerned when designing and fixing up daily life and the public activity area facilities of the elderly. To some extent, it can reduce the falling risk of the elderly. In addition, the elderly stand up from chair or sofa should move forward to walk till the body fully extended and firm, it can get great balance stability and reduce the probability of the fall risks. The hip and lower limb extensor muscles, especially the lower extremity joints flexibility should strength in the elderly daily life fitness exercises. Such as Tai-chi can improve the strength of the lower extremity joints and the ability to keep balance.