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Czarazuk
November 20th, 2007, 04:20 PM
While a bodysuit may provide a hydrodynamic advantage over bare skin, I have not yet seen a discussion regarding the additional weight of using a bodysuit. More particularly, water infiltrates the suit and remains within the suit as you swim. That is, water infiltrates the structure of the textile and also gets trapped between the suit and your skin. As you move through the water, the energy you exert also has to move the water within the suit.

Let us look at some basic math: the average body surface area for a man is 1.9 meters squared (this is from an article in Wikipedia on body surface area, BSA), which equals 19,000 cm squared. If an average of only one millimeter of water is trapped by the suit (i.e., within the structure of the textile and between the suit and your body), then a volume of 1,900 cm cubed of water is being pulled along with you.

Given that water has a mass of approximately one gram per cm cubed, this adds 1900 extra grams to your body. This translates to about 4.2 pounds of extra weight that you have to pull through the water.

The question is: would you rather have slightly better hydrodynamics or lesser weight. Personally, I'll go for the lesser weight any day. Your thoughts?

rtodd
November 20th, 2007, 06:39 PM
A body suit should be rediculously tight. You would have to confirm the 1mm number.

jim clemmons
November 20th, 2007, 06:51 PM
I'd take the weight since you should be basically neutral buoyancy and so the weight doesn't matter (in minimal amounts).

cowsvils
November 20th, 2007, 07:39 PM
I think Jim is correct here, because wetsuits add to bouyancy significantly (from the little bit of reading I have done and the small experience i have) that weight addition is offset and then some.

quicksilver
November 20th, 2007, 09:23 PM
A few comments I've heard about full suits...

They work best when you enter the water dry.
They should fit tight.
An older suit with (with stretchy fabric) can trap water and bog you down.


Wet suits for open water swimming are different because they can trap air.
You can pull on the neck and chest.... and fill them up with air pockets...effectively turning your suit into a buoyancy device.

Allen Stark
November 21st, 2007, 12:03 PM
The suit should be dry when you get up on the blocks.Then it is slightly buoyant so its weight is irrelevant in distances less than 200.Beyond that some suits gain enough water to make them less than effective.

jim thornton
November 22nd, 2007, 12:35 PM
I have swum in both the Speedo Aquablade, which is almost impossible to get anymore; and the Fastskin 1.

The former seemed to me considerably lighter in the water, and I prefer it still for longer events.

The FS1 seems to give me slightly better times, but I don't feel quite so slippery in the water as I do in the Aquablade.

I have never tried the FS2 and wonder if anyone could comment on this relative to the two I have tried. I was reading about the FSPro, M.Phelps' comments on this at the Speedo website, and a Washington Post article.

It's still really expensive--$300 or so (slight discount here and there.) But I am wondering if any of you have tried this one, which is supposed to be much lighter than its predecessors.

Also, if anybody knows where you can still get Aquablade long john style men's suits, I would much appreciate the reference!

Allen Stark
November 22nd, 2007, 02:24 PM
I have all three as jammers(which are almost affordable).I don't notice much difference between FS I and II.FS Pro is much lighter and I like it more,but it does collect bubbles you can feel under the suit and that may be more of a problem with a full body suit.

The Fortress
November 22nd, 2007, 03:57 PM
I love a bodysuit for meets! I have a fairly new FSI I purchased for $60. I've swum fast times in it, so it feels lucky, but it also feels heavy. My FSII was fine, a bit lighter than the FS I, but it's completely shot now and unusable. My fav is by far the Pro. It is ultra lightweight. If you hold the FS I and the Pro is your two hands, there is a very noticeable difference in weight. The Pro feels sleek in the water to me too. Not sure about this, but I think its lightweight nature helps more overly slightly longer distances. I believe in the Post article, Zeigler says it made her legs feel lighter. There is some bubbling, but it does not bother me. So I much prefer suit to skin, and I think it's slightly faster.

I'm sure this varies person to person. I know Ande hated his Pro. I know some people that have had ripping issues with them. There are plenty of other good technical suits too. I've heard good things about the Arena suits. But, right now, I'd take the Pro over the FS I or FS II. It's got the same compression, but is lighter and zippier.

One note on these suits, which most know. They just don't last long in terms of water repellancy. A college coach told me recently that his kids use a fastskin for 2-3 meets, and then they get new ones. I plan to use mine longer than that. But it's a hefty investment for a short shelf life. But you do feel like you're in a superman costume with it on! :woot:

Jim: I have a teammate that likes those long john style suits, but he can't find them anymore. His fav suit is a "paper" suit from decades ago that he saved. The texture remind me of the new Pro.

ande
November 23rd, 2007, 12:50 PM
FS fabric is thin and tight
it repels water, it creates a better surface than skin
spray the fabric with tent water proofing and it will be even more so

compare times of a swim with and with out a FS
get plenty of rest so fatigue isn't a factor



While a bodysuit may provide a hydrodynamic advantage over bare skin, I have not yet seen a discussion regarding the additional weight of using a bodysuit. More particularly, water infiltrates the suit and remains within the suit as you swim. That is, water infiltrates the structure of the textile and also gets trapped between the suit and your skin. As you move through the water, the energy you exert also has to move the water within the suit.

Let us look at some basic math: the average body surface area for a man is 1.9 meters squared (this is from an article in Wikipedia on body surface area, BSA), which equals 19,000 cm squared. If an average of only one millimeter of water is trapped by the suit (i.e., within the structure of the textile and between the suit and your body), then a volume of 1,900 cm cubed of water is being pulled along with you.

Given that water has a mass of approximately one gram per cm cubed, this adds 1900 extra grams to your body. This translates to about 4.2 pounds of extra weight that you have to pull through the water.

The question is: would you rather have slightly better hydrodynamics or lesser weight. Personally, I'll go for the lesser weight any day. Your thoughts?

jim thornton
November 23rd, 2007, 11:33 PM
Ande--

you say that FS material is thin and light. Do you mean FS Pro material, which I think is different from its I and II predecessors.

also, is it A) legal in competition to spray tent sealant (or any other material) on a swim suit? and B) have there been any studies that demonstrate this is an enhancement? If so, I can't believe that Speedo, Tyr, etc. wouldn't be promoting the bejesus out of "EZ Swim Spray (TM)" body suit coating mist.

my understanding from yesteryear investigations is that the forms of drag these suits cut are not surface drag (aka, skin friction)--in fact, the little sharkskin dermicles in the FS I suit actually increases friction (like the dimples on a golf ball). But that the other two forms of drag--eddy? form? wave? not sure the exact terms--are reduced so much more that the frictional increase is not important. I'm wondering if the tent sealant (or other slipperiness-inducing agents) has a positive role in the trio of drag forces here.

Perhaps our physicist colleagues will know the answers here.

knelson
November 24th, 2007, 12:05 AM
If so, I can't believe that Speedo, Tyr, etc. wouldn't be promoting the bejesus out of "EZ Swim Spray (TM)" body suit coating mist.

Oh no, they're too busy convincing you that you need to buy a brand new suit to get this water repellency back. Selling a new $300 suit is going to make them a lot more money than selling you a $9.95 bottle of Nikwax.

And you're a little confused on the shark denticles and dimples on a golf ball. What these do is trigger turbulent flow. This causes flow separation to occur farther back and this reduces the size of the wake. The net effect is to reduce drag, not increase it.