← What a Time Standard Means · Lesson 4 of 4
A best time is a minimum
A swimmer’s times scatter a little from race to race. A “best time” is the fastest of several, so it is the luckiest one. For a swimmer who averages 37.2 seconds with a typical spread of 0.45, the best of three is about 0.38 seconds quicker than the average, and the best of ten about 0.69 quicker.
So the next swim is usually a little slower than the best, and a big drop is often followed by a smaller one. That is not a slump — it is what picking the best of many does. Compare a swim with that swimmer’s own usual times, not only with the best.
A swimmer’s best is 37.20, the quickest of five meets. At the next meet she swims 37.55. What is the most likely reading?
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