Newly Walking Toddlers: How Do Different Strategies Combine When Developing Pendulum Mechanism?

摘要

During the first months of independent walking toddlers use different gait strategies and then converge to more similar walking forms, developing manifestation of the pendulum mechanism. The extreme modes of walking usually adopted by toddlers are three: the Twister, the Faller and the Stepper. The aim of this work was to analyze quantitatively how toddlers explore those strategies and combine them when developing the pendulum mechanism. Twenty healthy infants participated in the study. Each infant performed 5 tests in 6 months after the onset of walking. Two tri-axial wireless inertial sensors were mounted respectively on the lower back and on the right leg. The participants were asked to freely walk in the room. For all the participants 10 consecutive strides were analyzed. A typical parameterized waveform was designed for each gait strategy. Each waveform was fitted into toddler data and then subtracted from the signals. Percentage of residual signal power was calculated as an indicator of how much the gait deviated from the intended strategy. Preliminary results of signal power analysis are based on three toddlers, each one showing at the first week of independent walking a different gait strategy. Each toddler explored and combined mostly two of the three strategies presented when developing the pendulum mechanism. The two combinations found were twister and faller or stepper and twister: faller and stepper strategies appeared to be alternative in the development of mature gait. The analysis of more data will confirm this first conclusion.