Baby carriage: infants walking with loads.

Maintaining balance is a central problem for new walkers. To examine how infants cope with the additional balance control problems induced by load carriage, 14-month-olds were loaded with 15% of their body weight in shoulder-packs. Both symmetrical and asymmetrical loads disrupted alternating gait patterns and caused less mature footfall patterns. Walking was most severely compromised by back loads. Infants with less walking experience, lower levels of walking proficiency, and chubbier body proportions were more adversely affected. In addition, infants displayed a unique postural response to asymmetrical loads. In contrast to older children and adults, infants leaned with loads rather than in the opposite direction to the loads. Findings are discussed in terms of development from accommodation to compensatory strategies.