Abstract
Many people get injured due to fall each year. Some individuals show a better performance in handling stability perturbations, which is related to the reaction pattern, and mainly to the physical capabilities, such as muscle strength, delay time, etc. Properties affecting the success of individuals' effort to regain their balance following a perturbation onset have been considered by the researchers. However, there is no solution so far that, for a given mechanical/control properties -as a representative model of an individual- determines this person is definitely robust regarding which domain of perturbations, and falls in case of others. Practical efforts should try to extend the domain of balanceable perturbations for an individual. Presently reported work addresses the question of from which initial states an individual can regain its balance. The state space may be divided into two regions, balanceable and unbalanceable, the boundary of which is in close relation with the individual's mechanical/control characteristics.
