In humans, walking is bipedal locomotion in which the legs alternate (180aa out-of-phase) their step cycles as one foot moves ahead of the other. A step cycle includes a swing phase in which the leg leaves the ground and swings forward to re-establish contact with the surface at which point the leg enters the stance phase where the body‚was weight is supported. One or the other foot is always in contact with the support surface. During walking, the stance phases of the two limbs overlap for a period called ‘double support’ as well as periods of ‘single support’ when only one limb is in contact with the support surface.
See Cruising, Gait, Gross motor abilities, Hopping, Locomotion, Motor milestone, Skipping, Running