Examined longitudinally the effects of infants' age, body dimensions, and experience on the development of crawling. Although most infants displayed multiple crawling postures en route to walking, development did not adhere to a strict progression of obligatory, discrete stages. Duration of experience with earlier forms of crawling predicted the…

Used kinematic measures to compare relative contributions of growing body dimensions, age, and walking experience in walking skill development in 9- to 17-month-olds, kindergartners, and college students. Found that with increased age, size, and experience, children's steps became longer, narrower, straighter, and more consistent, reflecting a…