Comparison of Center of Force Trajectory during Sit-to-stand Movements Performed by Elderly and Old-old Elderly Subjects

[Purpose] This study compared the center of force (COF) trajectory during sit-to-stand (STS) movements performed by elderly and old-old elderly subjects. [Subjects] We recruited 9 elderly and 10 old-old elderly subjects with no knee joint pain or lower limb orthopedic problems. [Methods] The CONFORMat system was used to measure the length of the COF trajectory as the subjects performed the STS task. [Results] The total length of the COF trajectory during the STS movement was significantly greater for the old-old elderly group than for the elderly group. [Conclusion] Our results highlight the need for novel strategies or the development of assistive devices to reduce the COF trajectory during the STS movement for old-old elderly individuals.