The impact of object carriage on independent locomotion

• Carrying light objects impacted children's arm postures, with children adopting less sophisticated arms positions during object carriage.
• Carrying light objects failed to impact walking skill parameters.
• Arm position was related to walking skill, but only for older children and when not carrying objects.
• Relation between arm position and walking skill parameters is impacted by object carriage, even small, light loads.

The current study examined whether carrying objects in one's hands influenced different parameters associated with independent locomotion. Specifically, 14- and 24-month-olds walked in a straight path under four conditions of object carriage – no object (control), one object carried in one hand (one object-one hand), two objects carried in each of the hands (two objects-two hands), and one object carried in both hands simultaneously (one object-two hands). Although carrying objects failed to influence a variety of kinematic parameters of gait, it did affect children's arm postures, with children adopting less mature arm positions when carrying objects. Finally, arm position was related to walking skill, but only for older children when they were not carrying objects. These findings indicate that although a relation does exist between arm positions and gait parameters, this relation is easily disrupted by carrying loads, even small ones.