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If your target race is a marathon, try our marathon time predictor. If it still feels too slow later on in the race, then you can start speeding up.) (If it feels too slow, that’s probably your taper talking. If you start running and the pace feels too quick, back off. Just because the calculator spits out a fast time doesn’t mean that you’ll automatically be able to run it - you still have to put in the work.įinally, remember that this is just a prediction, not an absolute truth. A flat mile track race on a cool day isn’t going to tell you much about how a hilly marathon in heat is going to go.Īlso, keep in mind that training for different longer race distances looks very different from training for shorter ones, and vice versa. No matter which method you’re using, you’ll get the most accurate results by choosing a recent race that was as similar as possible in race distance, weather, and course difficulty. Still, we include it in the calculator results so you can use it as a reference. The equation is simple and easy to use (which is why so many are still using it), but it fails to take into account age and gender. This approach is different from what you’ll find on other race time predictor tools, most of which use an equation published by Peter Riegel in 1981: T 2 = T 1 x (D 2/D 1) 1.06 where T 1 and D 1 are your finish time and distance in a recent race, and T 2 and D 2 are your predicted time and distance in an upcoming race. (Scroll all the way down in the Race Distance list to get to Other.) The same is true for your recent race distance. This allows us to generate predictions for any race distance, not just the common ones.
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If a world record doesn’t exist for your target race distance, we make our best guess at what it would be by looking at the world records for the next longest and next shortest available distance. We then take that score and figure out how fast you’d have to run the new distance to earn it again. We use the logic from our age-graded calculator to get an age-graded score relating your recent run to the world record at that distance, multiplied by a factor to adjust for your age.
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