Movement control strategies during jumping in a lizard (Anolis valencienni).
Whereas maximal performance is subjected to specific control criteria, sub-maximal movements theoretically allow for an infinite number of control strategies. Yet sub-maximal movements are predominant in the locomotor repertoire of most organisms and often little understood. Previous data on sub-maximal vertical jumping in humans has suggested that a movement effectiveness criterion might best explain the observed control strategy employed. Here we test the generality of this criterion in jumping by inducing lizards to jump both at a range of distances as well as a range of take-off angles. Our results show that while movement effectiveness appears to best explain jumping for different take-off angles, a 'push harder' strategy (i.e. mostly increasing the force output of the system), is used in the control of distance jumping. Thus, our data support the generality of the movement effectiveness criterion for vertical jumping, but not for distance jumping. Sub-maximal distance jumping in the lizard Anolis valencienni appears to be governed by a relatively simple control strategy that allows a rapid response. This accords well to the ecological circumstances in which long jumps are typically used (escape from predators).
Toro
Esteban
E
Stanford University, Department of Developmental Biology, Stanford, CA 94305, USA.
Herrel
Anthony
A
Irschick
Duncan J
DJ
D000818:Animals; D001696:Biomechanical Phenomena; D008116:Lizards / Q000502:physiology*; D008124:Locomotion / Q000502:physiology*