Falls and related injuries cause loss of independence, reduce quality of life, and increase mortality among elderly people. Fall-related injuries cost Canadians $3.6 billion in 1995. Consequently, reducing the incidence and severity of falls is an important health priority. Dawn Mackey is comparing young and elderly study participants to measure the variables that govern our ability to recover balance following unexpected movements. Maintaining a stable upright posture is essential to daily activities such as walking, turning and rising. However, postural stability declines as we age. Dawn will assess whether balance recovery depends on the strength and speed of muscle response, simultaneous contraction of front and back ankle muscles, where someone's mental attention is focused, and the intactness and speed of sight and hearing. She hopes the research can be used to design exercise and rehabilitation programs to prevent falls among elderly people.