Influence of Additional Ankle Weights on Kinematic Variables of Late Preterm Infants Aged 3-4 Months.

The authors analyzed and compared the effect of additional weight on the spatiotemporal parameters of the kicking movement of late preterm and full-term infants. The experiment was divided into 4 conditions: training, baseline, weight, and postweight. In the W condition, a weight of one third the lower limb mass was added to the infant's ankle. During the baseline and postweight conditions, the ankle weight was removed. Late preterm infants do not differ from full-term infants in relation to spatiotemporal variables at 3 and 4 months. However, during the weight condition, the straightness index and the hip-ankle and knee-ankle correlations decreased in the preterm infants at both ages. In contrast, the straightness index increased in the postweight condition compared to the baseline values at both ages.