title: Spatio-temporal constraints on upright children's coordination when hitting a moving target.
abstract: To determine if the spatial and/or temporal context affected the coordination patterns of children under five in upright interceptive tasks, 3-year-olds hit a ball dropped from a ramp from five heights (1.5, 2, 2.5, 3, and 3.5 m) to control drop time. We studied the initiation time of hitting a ball with a cinematic analysis of the different joint movements (foot, knee, hip, shoulder, and hand). Two patterns of joint coordination were observed according to the rolling height of the ball: a de-synchronized pattern for heights of 2 m or above where the foot was the first to move and the hand the last, and a "synchronized" pattern, for the lowest height (1.5 m) where all joints started moving at the same time due to a strong temporal pressure. These two coordination patterns highlight a functional adaptation of body joints according to the spatio-temporal constraints among children from the age of three.
authors.affiliation: Laboratoire Action, Motricité, Adaptation, JE 2378, UFR STAPS, Université René Descartes Paris 5, 1 rue Lacretelle, 75015 Paris, France. florence.rosey@wanadoo.fr
authors.forename: Florence
authors.initials: F
authors.lastname: Rosey
authors.forename: Jean
authors.initials: J
authors.lastname: Keller
authors.forename: Eveline
authors.initials: E
authors.lastname: Golomer
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009039:Motion Perception; D009048:Motor Skills / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*; D014110:Touch