Posture Noise and the Measured Probability to Fall

Experimental evidence is presented connecting small fluctuations in the posture of a quiet standing subject and the probability that the subject will have an accidental fall within a time period of one year. The data can be understood on the basis of random velocity fluctuations providing kinetic energy in dynamical posture modes. The kinetic energy can activate a transition over the a potential energy barrier which keeps subjects in a metastable standing mode. The probability for a fall then follows an Arrhenius activation law.