By the end of his m campaign, De Grasse saw three athletes fail to race — all because of a costly flinch. Coming off the starting blocks quickly is an ability that requires strict biomechanics and powerful first steps. But the moment before, when the brain tells the legs to fire? World Athletics, the governing body that sets the rules for the Olympics and world championship meets, has waddled on false starts over the past two decades.
But after multiple strategies — the most recent adjustment charged the first false start to the field while the second axed the offender on the second failed attempt, regardless of who committed the first — these Olympics have a zero-tolerance policy if the runner jets off any faster than 0.
If they fly under, officials may give them a yellow card as a first warning. Sprinters will practice from starting blocks at least twice a week in training, but those sessions involve getting their legs bent at their most powerful and efficient angle, aligning their shins and plunging as much force as possible into those first few steps. Part of this lies in the science behind human reaction time. The current statistics on max human reaction time lies around 0.
Instead of trying to control reaction times, coaches lay focus to how athletes respond to uncontrollable barriers, the minor ones including random noises or how long they hold the set position. The most treacherous one, however, is always on full display at the Olympics: stress. That will be like the real thing.
In major athletics competitions, reaction times RT are currently detected using IAAF accredited false start detection systems. These systems determine athletes reaction time using encased accelerometers or force sensors fixed to the rear of the starting block rail to detect changes in force or acceleration exerted on the blocks through the feet.
RT's can now be instantly calculated accurately to 0. Research has found that a reaction time faster than one-tenth of a second is impossible for a human, and the runner is therefore deemed to have anticipated the gun. The most common way to detect a false start in major track meets is by a device called ReacTime.
The ReacTime unit sits on the back of the starting block. It is connected either by wires or by radio signals to a main computer near the race starter usually an individual with a starting gun. The device measures the pressure that an athlete exerts on the starting block when in a set position and relays this information in real-time to the main computer, measured down to one-thousandth of a second.
When the starting gun is fired, the main computer marks the exact moment of the start, and also calculates the time it will be one-tenth of a second later. Each pressure-sensitive unit continues to relay information back to the main computer as the runners leave their respective starting blocks and begin down the track. As the runners leave the blocks, the pressure exerted on the blocks increases and then decreases; on a graph, this rise and fall of pressure forms a parabola.
The computer analyzes the data for each runner and determines the exact moment when the pressure begins to increase at a certain rate. This is to make clear that any athlete making a further false start will be immediately disqualified and the familiar red marker displayed. At the time of writing, many IAAF Member federations are educating their officials and their athletes about the new system in domestic competitions, prior to the start of the international indoor circuit in February.
Note: for Combined Events, the procedure is slightly different.
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