Testing a sprinter’s progress during training is often done by precisely measuring the time to sprint specific distances. However, some tests are performed by precisely measuring the distance an athlete can run in a specific time. An example of such a test is the 25 second test, which measures the distance an athlete can sprint in 25 seconds. This article describes how to precisely measure that distance using Freelap.
Prior to the use of automated timing systems, these tests were typically done with a hand-held stopwatch. When using a hand-held stopwatch, coaches monitor the time on their stopwatch as the athlete is sprinting and the coach shouts a “mark” command when the stopwatch reaches a specific time (e.g. 25 seconds). Then, the coach measures the place on the track where the athlete was at the time the coach shouted the mark command. Although relatively simple, the problem with this method is the relatively large margin of error. An athlete may be traveling between seven and ten meters per second, and identifying the location at which the athlete had run in the allotted time period may be off by several meters or more.
The Freelap Timing System makes it possible to measure these distances with considerably greater accuracy. The method begins with a good estimate of the distance the athlete should be able to run in the allotted time period. Using past performances and recent workout data, the coach should be able to guess the distance plus or minus five percent or thereabouts. For example, if a high school athlete ran 206.35 meters in a previous 25 second test, and if the recent workout timing information indicates the athlete should be able to improve the distance by a couple meters, the coach may estimate the new distance will be 208 meters, plus or minus.
Given this estimate, the coach places the Freelap TX Junior transmitter at 208 meters. The athlete then runs the test wearing the Freelap stopwatch and records the time. Assuming the coach made a good distance estimate (any track coach with modest experience should be able to guess relatively close), the time should be relatively close to 25 seconds. For this example, let’s say the sprinter than the 208 meters in 24.86 seconds. Since the time is slightly less than 25 seconds, this means the sprinter ran slightly more than 208 meters in 25 seconds.
To determine the actual distance, we can use the calculation
208 meters * (25 seconds / 24.86 seconds) = 209.33 meters
In other words, the sprinter was able to run 209.33 meters in 25 seconds.
If the coach had guessed long and the time had been greater than 25 seconds, then using the same equation above, the resulting distance would have been less than 208 meters. For example, if the sprinter had run the 208 meters in 25.12 seconds, then using the same equation
208 meters * (25 seconds / 25.12 seconds) = 207.01 meters
Of course, this method can be applied to test of any duration. Simply place the finish transmitter at your best guesstimate, and then apply the conversion shown above to determine the actual distance with considerably more accuracy than using a hand-held stopwatch.
Bracketing the Guesstimate
If the coach does not have a good estimate for an athlete, perhaps because it is the first test of the season or the athlete is returning from an injury, the guesstimate can be bracketed using two or more TX Junior transmitters at the finish. For example, if the coach estimates that the athlete will run 210 meters in 25 seconds, plus or minus 15 meters, the guesstimate can be bracketed by placing a transmitter at the 205 and another at 215. If the athlete runs a slow 25 second test and the time on the first transmitter is 25.57, then the distance would be calculated using the time of the first transmitter. If the athlete runs a fast 25 second test and the total time at the second transmitter is 24.78, then the time from the second transmitter would be used to calculate the distance.
When testing a larger group of athletes, it is possible to use a larger number of transmitters at the finish to bracket all the athletes being tested. For example, transmitters could be placed at the 185, 200, 215, and 230 to bracket all the athletes that run the 25 second test within the range 180 to 235. The transmitter with a total time that is the closest to 25 seconds would be time the that would be used to calculate the distance covered in 25 seconds. For example, if an athlete gets to the third transmitter that was placed at 215 meters in 24.89 seconds, then the equation would be
215 meters * (25 seconds / 24.89 seconds) = 215.95 meters