During the horse`s jumping the flow of air creates friction on a surface of the horse`s body. The rough surface of the horse`s body smoothes out at the expense about force of riction of a flow of air at a jump. At such long duration process the body of the horse gets a figure of an ellipse. The figure is considered as the best form against resistance of  flow of air.During the horse jumping the flow of air creates friction on a surface of the horse`s body opposite the horse`s movement.