In horse racing, while the final time of a race is important, the internal segments are even more crucial.
Races are timed in segments, and those are often called fractions. When you hear it said that a horse ran fast fractions, that means it broke quickly out of the gate and ran faster than usual in the first part of the race. Conversely, if someone says the final fraction of a race was quick, they are referring to the last segment before the finish line.
Sprint races, which are run around one turn, are usually timed at the quarter mile, the half-mile, and then the final segment, which can be as short as one-half furlong, or 1/16th of a mile, or as long as 3 ½ furlongs.
Route races, which usually go around two turns, are typically timed at the half-mile, three-quarters of a mile, a mile, and then the final segment if the race is longer than that.
As a rule of thumb, fractions faster than 23 seconds in sprints and 24 seconds in routes are considered fast.
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