Abstract des Autors

Whereas infinite combinations of step length and step rate can exist when walking at a given speed, adult humans usually walk at an invariant ratio of step length divided by step rate (walk ratio) over a wide range and gender difference of the invariant walk ratio, and to compare the ratio between free walking and forced walking. Sixty-four healthy students walked on a flat walkway (0.6 x 16m) at different speeds using freely chosen step rates (free walking), and with imposed step lengths and step rates (forced walking). The walk ratio was invariant, with little intersubject variability during free walking at preferred and faster speeds (53 to 137 m/min for males, and 82 to 134 m/min for females). There was no gender difference in the walk ratio in this speed range after adjusting for height. At lower speeds, however, the walk ratios were much more variable and larger than those at preferred and faster speeds. The walk ratio for forced walking varied with speed and was far more variable than for free walking, suggesting that invariant walk ratios are specific to free walking. This invariant relationship between step length and step rate is discussed in terms of energy expenditure, stability, and attention during human walking. Verf.-Referat