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Comment by ZeroGravitas | Hacker News Reader

Nice presentation, but I feel the underlying absurdity of world records starts undermining the point once you go this deep.

How many meters did Usain Bolt have to run in training before he ran his 100 meter record winning run.

How much of the time is a factor of the cubes randomisation, or the speed at which you pick up and drop the cube.

For the world's shortest river, how do you define river?

I think lay people would be surprised by the effectively arbitrary legal minutiae of most sports and competitions.

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> How many meters did Usain Bolt have to run in training before he ran his 100 meter record winning run.

That's not really an accurate comparison. The current setup is more akin to a 100m running challenge where he was allowed to run 50m before starting the actual 100m to get up to speed.

The inspection time is not training, it's literally the time spent solving the cube.

A better analogy would be to ask whether we should count the time Bolt spent stretching before the gun was fired. If Bolt hadn't stretched, he would've been slower but he still would've been pretty fast.

Its a broader point that the limits are arbitrary, like high tech clothes or bike designs getting created and banned (or not), but there are actual sports with rolling starts or maximums and minimums defined but no bonus for using less than the max.

The long jump is measured from the board, not from where you jump. Getting close to, but not over the edge is part of the arbitrary rules of the sport.

> The current setup is more akin to a 100m running challenge where he was allowed to run 50m before starting the actual 100m to get up to speed.

It looks like an interesting idea. The long jump competitions have something like that. Can someone organize it? Do you have to go slowly the first 40 meters and increase the speed just in the last 10 meters before the start line? Can the data from the 200m run be used to estimate this?

200m split times are routinely tracked - see e.g. https://world-track.org/2022/07/what-are-noah-lyles-splits-f... (it turns out the US national 200m record was broken a couple days ago)

And it is absolutely the case that the times for world class second-100m of a 200m sprint are generally lower than even world record 100m sprints (in that report above, out of the field of 8, 6 runners beat the 100m world record over their second 100m)

Usain Bolt's world record 100m from a stationary start is 9.58s. His world record 200m splits were 9.92s and 9.27s.

Over the middle 100m, his time was 8.84s.

(see https://speedendurance.com/2009/08/21/usain-bolt-200-meter-s...)

So yes, a flying start makes a massive difference. 200m runners are generally slowing down in their second half (Bolt's last 50m took 4.75s, while he covered 100-150m in 4.52s, and 50-100m in 4.32s), but their average speed over the final 100m is still faster than a 100m runner. In a 100m sprint the runner may still be accelerating by the time they reach the line.

I just remembered that all (some?) boat races start like this. You must cross the starting line after the initial time, but you can already have speed.

Yes, though this is for the practical purpose that having a bunch of sailboats trying to stay completely still is a recipe for chaos.

This is such a good analogy that it sounds like an interesting event in itself.

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