How high could I jump if my legs were as powerful as a house cat's hind legs?

[Desmostylus]

Originally posted by Blake
**You apparently cannot understand that a reference stating that height remains constant irrespective of the animal means that height remains constant irrespective of the animal.

You apparently also cannot understand that a reference stating that all members of any jumping species raise their centers of gravity about one meter when they leap means that no members of a jumping species raise their centers of gravity more than about about one meter when they jump.

Since that is the case I give up. You are beyond my ability to help.**

Originally posted by Blake

about 4 foot doesn’t seem unrealistic

I’m quite happy to accept that. In fact I never said any differently. The dispute was with the OP and numerous anecdotes of cats jumping 6 feet. Once we get to 5’ we are talking another 50% height, which is no longer equivalent. 6’ is over an 80% increase.

Vertical jumping in Galago senegalensis: the quest for an obligate mechanical power amplifier

In assessing the mechanical capabilities of musculo-skeletal systems, the analysis of maximal jumping is exemplary, as the natural demands imposed on the system are maximized too (see, for example, Sellers 1992). The involved stresses are high and impact-like (cf. Bennet-Clark 1976, 1977), and the energy required for every new leap has, theoretically, to be delivered de novo by the muscles (see, for example, Bennet-Clark 1976, 1977; Gunther et al. 1991; Crompton et al. 1993). In his theoretical analyses on the energetics of jumping and the effects of size, Bennet-Clark (1976, 1977) noted that animals, perfectly capable of delivering the jumping energy instantaneously, can have difficulties when the rate at which the work has to be done to attain a certain height exceeds the muscle power. In other words, instantaneous power output capabilities of muscles can constrain jumping performance. This is primarily true for the smaller animals, as the power that is instantaneously required is directly proportional to the available acceleration distance (i.e. leg length in most of the cases). Therefore, jumpers might benefit from a mechanical power amplifier that releases previously stored energy at an increased rate (see, for example, Bennet-Clark 1976, 1977; Emerson 1985; Alexander 1992).

The bushbaby Galago senegalensis (Lorisiformes) is well-known for its enormous jumping capabilities (see, for example, Hall-Craggs 1964, 1965, 1974; Jou¡roy & Gasc 1974; Jou¡roy et al. 1974; Gunther & Niemitz 1982; Jou¡roy & Gunther 1985; Gunther 1985, 1989; Jou¡roy 1989; Demes & Gunther 1989; Gunther et al. 1991, 1992; Sellers 1992; Crompton et al. 1993). The highest reliably reported vertical jump for a 0.250 kg animal is 2.25 m (Hall-Craggs 1965), which corresponds to a displacement of the centre of gravity during the flight phase of approximately six body lengths (tail not included). Based on this information, and assuming a constant acceleration during the push-off, Bennet-Clark (1976) estimated a specific power output of 2350 W per kilogram of muscle, provided that the jump is instantaneously powered by the contractile components of the muscles. (It was assumed that 40% of the body mass consists of muscles involved in jumping.) Such a value is well above the maximally attainable output deduced for vertebrate muscle (for example, 860Wkg[sup]-1[/sup] theoretical maximum for pigeon flightmuscles (Pennycuick & Parker 1966); 270-371 Wkg[sup]-1[/sup] calculated and measured for frog hindlimb muscles (Lutz & Rome 1994; Marsh & John-Alder 1994); 380 Wkg[sup]-1[/sup] for typical fast glycolitic fibres (based on data presented in Herzog (1994))).

Game, set and match. Now go away. :rolleyes: