Had a quick search and couldn’t find any previous discussion.
The pool I swim (Manchester, UK) in is a 50m pool that more often than not will be split down the middle. One half is a constant 2m in depth and the other half is typically v. shallow (slightly above waist height?).
When the deeper half is being used for swim clubs etc, everyone else gets penned in to the shallower half where there are a few lanes set up.
I have noticed that I find it considerably harder to hold my form in the shallower pool - and just find it tougher to swim in all-round.
When I swam at the weekend in the larger pool I could comfortably hold 100s (freestyle) at ~1:30 but really struggled in the shallower pool (which is actually 2m shorter at 23m) a couple of days later.
I know that pool size and particularly depth can affect the speed of a swimmer - but I though this only impacted elite swimmers, and only by fractions of seconds.
Is is all in my head or has anyone else experienced this?
I would dare say BOTH. There is some very real increase in drag as the water you are displacing is confined to shallower depths. But probably not as signifigant as you are experiencing.
I used to kayak a fair amount, and when I would get into shallow water my speed would drop dramtically, same principle with shallow pools. Just no where for that water to go, so it pushes back on you.
All the real swimmers I swim with say that deeper pools are faster. Something about the wave displaced hits the bottom and then comes back.
Personally I think it’s hogwash but most of my best swim meet times have come from the deepest pools. But then only by a handfull of seconds in the 500 and 1650.
Deep pools are faster, but up to a certain point. I know when the were planning the IUPUI pool in Indy, Doc did studies on how deep was deep enough? I don’t recall specifics, but something like 9 ft (?) (also seem to remember they went a little deeper than necessary).
But, with all that - if you are training for triathlon you need/want all the waves.
After all, we do race in open water without the wave quenching lane lines and gutter systems! So enjoy and get adapted. Go with the flow.
Deeper pools are definietly faster because there is less turbulence but keep in mind, places in swimming races are calculated to the hundreth of a second. So while the difference is real, unless you a talking a 30 inch deep pool vs a 12 foot deep one, it is in the same category as wearing aero shoe covers in a time trial. Important, but not so much for the average Joe.
Another very real issue for some people is psychological. The sight picture of having the bottom really close versus really far away, combined with the effect that has on perceived speed can lead some people to change their stroke a bit in pools of wildly diffferent depths. Pool depth can also really mess up your flip turns for the same reason which can also cause speed differences.
Deeper is faster. I can’t quantify a number but the wave you create can actually bounce back off the bottom and creates more turbulent water. If there is deeper water that wave or turbulence dissipates down. You have the same concept if you wakeboard or wake ski behind a tow boat. If the water is too shallow, the wake bounces off the bottom and creates very choppy water.
as everyone else has said, deeper pools are faster. There are actually minimum specs for depth to be a pool worthy of a major international competition (also water temp, lighting, lane width in addition to depth).
But, as a few others have pointed out, the increased turbulence in a shallow pool is good training for open water/swimming in a pack.
I think it might be a combination of a few things in reality.
The pool really can be very shallow, esp at the shallow(er) end - so shallow that I wince every time I flip-turn.
It can also be very busy.
This all makes it a bit choppier - as several said this is probably closer to OWS. This makes me think I need to go and practice some OWS as my stroke is likely going to deteriorate in the open water.
Interesting point as well about the differences in perception given the distance from the bottom - hadn’t thought about this but I can see that it would make a psychological difference.
Either way I know I much prefer swimming in the deeper pool - I was just trying to put my finger on why.
Pool depth can also really mess up your flip turns for the same reason which can also cause speed differences.
Yes. I’ve seen swimmers (and come close myself) used to coming off of a flip turn at a deeper angle to avoid the following water surge as you come into the wall, and scraping the bottom in a shallower pool.
Go to any kids’ age group meet where the pool depth is different at each end and 75% of the kids look different on the turns depending on which end of the pool they are at.
This is why I don’t do flip turns - I’m afraid of scraping bottom in the shallow pool I swim in. It has absolutely nothing to do with the fact that I look like a monkey humping a football when I attempt them.
