Affiliation:
1. Department of Biology, University of Antwerp (UIA), Universiteitsplein 1, B–2610 Wilrijk, Belgium
Abstract
Bushbabies (Galago senegalensis) are renowned for their phenomenal jumping capacity. It was postulated that mechanical power amplification must be involved. Dynamic analysis of the vertical jumps performed by two bushbabies confirms the need for a power amplifier. Inverse dynamics coupled to a geometric musculo–skeletal model were used to elucidate the precise nature of the mechanism powering maximal vertical jumps. Most of the power required for jumping is delivered by the vastus muscle–tendon systems (knee extensor). Comparison with the external joint–powers revealed, however, an important power transport from this extensor (about 65%) to the ankle and the midfoot via the bi–articular calf muscles. Peak power output likely implies elastic recoil of the complex aponeurotic system of the vastus muscle. Patterns of changes in length and tension of the muscle–tendon complex during different phases of the jump were found which provide strong evidence for substantial power amplification (times 15). It is argued here that the multiple internal connective tissue sheets and attachment structures of the well–developed bundles of the vastus muscle become increasingly stretched during preparatory crouching and throughout the extension phase, except for the last 13 ms of the push–off (i.e. when power requirements peak). Then, tension in the knee extensors abruptly falls from its maximum, allowing the necessary fast recoil of the tensed tendon structures to occur.
Subject
General Agricultural and Biological Sciences,General Biochemistry, Genetics and Molecular Biology
Reference55 articles.
1. Alexander R. McN. 1983 Animal mechanics 2nd edn. Oxford: Blackwell.
2. Alexander R. McN. 1988 Elastic mechanisms in animal movement. Cambridge University Press.
3. Alexander R. McN. 1992 Exploring biomechanics animals in motion. New York: The Scienti¢c American Library.
4. Leg design and jumping technique for humans, other vertebrates and insects
5. Storage of elastic strain energy in muscle and other tissues
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