Stability index results. Mean and standard deviation of stability indices of toddlers (black solid lines) and adults (dark grey solid lines) and elderly adults (light grey dotted lines). (RR: recurrence rate. DET: determinism. AvgL: averaged diagonal line length. MaxL: maximum diagonal line length. sLE3: Short term Lyapunov exponents calculated using a state space composed by the three linear acceleration components of the trunk. MSE: Multiscale entropy. V vertical, AP antero-posterior and ML medio-lateral axis).