Biomechanics Research in the Effects of Interactive Dynamic Balance Training on Postural and Gait Control in Older Adults

Aging populations has become a global issue. Fall is a prevalent concern among aging adults that can cause fracture, injury or mortality. Identifying the factors related to falls occurring within this aging population is essential for the development of effective regimes for fall prevention. Studies have shown that muscle quality and good posture alignments are critical for balance control in older adults. Older adults often combining with muscles weakness (sarcopenia), bone loss (osteoporosis) and lead to increased spine kyphosis causing vertebral fractures and poor balance control. Therefore, the long-term objectives of this work are to prevent fall in older adults by improving the function of degenerative muscles. The proposed research can provide needed information regarding the processes of balance control in this aging population, and can potentially be applied to individuals with poor balance who at high risk of fall. Three specific aims for this 3 years research project are described as follow:

Aim 1: Determine the relationships between muscle quality and balance performance as well as any association with fracture and fall history in older adults.

Muscle quality will be calculated from the information of muscle strength and body composition (strength/lean muscle mass). The investigators will compute the joint torque during functional activates using biomechanical data from the 3-D motion analysis, whereas the lean skeletal muscle mass will be determined by the bioelectrical impedance analysis (BIA). Clinical and functional assessments for balance performance will also be conducted. Fracture and fall history prior to the testing will be recorded retrospectively.

Aim 2: Identify the relationships between force usages during balance perturbation in older adults.

Lateral and forward/backward perturbation while walking will be used to elicit balance recovery responses. The degree of necessary joint force and how this relates to a person's functional capacity at specific joint levels will be determined by the torque demand to capacity ratio (DCR: task demands relative to strength capacity). The DCR provides a joint-specific unified scalar quantity representing the balance recovery demand normalized by the maximum muscle strength capacity of an individual. It would indicate whether a person can recover balance and to what extent of his/her maximum capacity is taxed.