The people who organize races like the motorola marathon have started to take cheating very seriously. many race organizers use a combination of methods to prevent cheating and to catch cheaters. one way is to attach a small computerized chip to a competitor's shoe. the chip is lightweight and a little bigger than a quarter. the chip tracks a runner's time at different points on the course. this determines whether he or she ran the entire distance. computer chips alone will not expose all cheaters, however. race officials also used video cameras at secret locations to watch runners. they also scatter volunteers throughout the course. the volunteers watch the runners and write down their numbers and times. sometimes race officials can catch a cheater just by looking at him or her. irregular sweat patterns in clothing, a lack of salt stains on a runner's face, and inappropriate clothes are telltale signs of cheating. those who dare to cheat better have the course memorized and be prepared to identify runners they saw along the way. race officials can be pretty nosy if they have suspicions.

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