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WHEN looking at the subject of athleticism, it is worth considering some remarkable feats of animal runners (or 'innately athletic locomotor extremists' as Alan Wilson of the Royal Veterinary College calls them), as well as of those animals that fly or dive. It is also interesting to consider some specific aspects of comparative exercise physiology.
Sprinting
Sharp (1997) timed the cheetah (Acinonyx jubatus ) to reach 64 mph (104 kph, 29 m/sec). The pronghorn antelope (Antilocapra americana ) reaches 55 mph (89 kph, 24.6 m/sec) and the North African ostrich (Struthio camelus camelus ) is the fastest running bird at nearly 40 mph (64 kph, 18 m/sec), while sailfish (Istiophorus species) reach a swimming speed of 67 mph (108 kph, 30 m/sec). Garland (1983) quoted a maximum speed of 20 m/sec or more (72 kph, 45 mph) for 17 species of mammal.
Other approximate maximum speeds are: Human beings 23.4 mph (37.6 kph, 10.4 m/sec);
Thoroughbred racehorse 43.4 mph (70 kph, 19.3 m/sec);
Greyhound 43 mph (69 kph, 19.2 m/sec); and
Camel (Camelus dromedarius ) 22 mph (35.3 kph, 9.8 m/sec).
Data from the sporting pages of newspapers show that most greyhound races are won at 15 to 16 m/sec, and most horse races of less than one mile (1.6 km) at 16 to 17 m/sec. The fastest horse speed recorded is 55 mph (88 kph, 24.4 m/sec) by the racing quarter horse ( Young 2003 ). Young also noted that the merriam kangaroo rat (Dipodomys merriami ), running at 110 body lengths/sec, would relatively outstrip the cheetah's 32 lengths/sec.
Cheetahs have a long streamlined head and body, 112 to 135 cm long. At top speed, a cheetah's extremely flexible spine assists a stride length of 7 to 8 m, which is so long that all four feet are off the ground for more than half the distance ( Rich and Rouse 2004 ). Other speed design features include: tough ridged pads for grip; non-retractable long blunt claws like running shoe spikes, which maximise traction; long legs, with most of the muscle proximally situated near the body (like antelopes, gazelles, greyhounds, horses and camels), giving very long tendons, which can store and release over half the energy at every...