Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Is a 'slow' swimming pool impeding world records?

sports.yahoo.com

Post reply on HN
Print view View original

11–20 of 344 posts

Re: Is a 'slow' swimming pool impeding world records?

#11

Post by mysterydip »

samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Would the swimmers in the center lanes have any advantage by being furthest away from the wall-induced chop?

Re: Is a 'slow' swimming pool impeding world records?

#12

Post by School-Cotton »

samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Why does it matter how deep the pool is?

Edit: the article addresses this, so if anyone else is curious like I was, I suggest clicking.

Re: Is a 'slow' swimming pool impeding world records?

#14

Post by hgomersall »

mysterydip wrote: post #11
samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Would the swimmers in the center lanes have any advantage by being furthest away from the wall-induced chop?

Supposedly, that's why the fastest qualifiers get the middle lanes.

Re: Is a 'slow' swimming pool impeding world records?

#15

Post by croes »

samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

>A lot of this is perception vs. reality,” he said. “If you were to talk to many very accomplished coaches, they would say the pool has to be a minimum 3 meters deep. Most of our research shows that anything over 2 meters is frivolous. … Obviously, some depth is very important. But after a certain point, it's diminishing return.

Maybe it's just the swimmers and not the pool as such

Re: Is a 'slow' swimming pool impeding world records?

#16

Post by creshal »

School-Cotton wrote: post #12
samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Why does it matter how deep the pool is? Edit: the article addresses this, so if anyone else is curious like I was, I suggest clicking.

Because it means waves bounce off the bottom faster (less distance travelled) and much more importantly, with far more energy (square cube law works against you). So the waters far more choppy far faster, since you have 50% less water volume to absorb all the energy.

Re: Is a 'slow' swimming pool impeding world records?

#17

Post by HPsquared »

School-Cotton wrote: post #12
samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Why does it matter how deep the pool is? Edit: the article addresses this, so if anyone else is curious like I was, I suggest clicking.

Edge effects affecting the flow field around the swimmer. I suppose the floor might trap turbulence near the surface rather than dissipating into the depths.

Re: Is a 'slow' swimming pool impeding world records?

#18

Post by defrost »

School-Cotton wrote: post #12
samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

Why does it matter how deep the pool is? Edit: the article addresses this, so if anyone else is curious like I was, I suggest clicking.

If it's too shallow the swimmers arms hit the bottom ...

Slightly deeper and there's drag from the floor as their arms barely miss it. That effect persists until it doesn't .. now it's deep enough.

It needs to be deep enough that vortex's created by swimmers have disapated by the time they reach bottom and reflect back to the surface so as to not interfere with following swimmers or swimmers returning.

Re: Is a 'slow' swimming pool impeding world records?

#19

Post by HPsquared »

davidmurdoch wrote: post #8
samldev wrote: post #5

I was a college swimmer, qualified for Olympic Trials in 2012 and 2016. There are absolutely slow and fast pools. It basically comes down to two things: 1. The depth - which is only 7ft in Paris, unusually shallow for a competition pool. 2. The sides. Does the water spill over the sides into the gutters, or smash into a wall and bounce back, creating more chop. A trained eye can see all the swimmers in Paris struggli…

To a lesser effect, there's also the surface tension of the water, which can be adjusted with salt and borates.

Density and viscosity must also play a role, or are those managed via temperature control?
Post reply on HN