Seltzer + Exercise = Do Not Want?

October 4, 2008 7:04 AM

Will drinking seltzer water before exercise hurt me?

According to my wife's friend, soda water slows down your metabolism. And this quick Google search says seltzer water is bad before exercise. Really? I've seen the MeFi thread on hydration and it doesn't really apply to me - I don't necessarily feel dehydrated after drinking seltzer - but is there anything else I don't know that I should? What about the dreaded carbonic acid? Is that a myth (according to the sometimes-questionably-accurate Wikipedia, it is mythical) or what?

posted by ostranenie to food & drink (9 comments total)

Um, if you drink carbonated tonic - or any carbonated beverage, for that matter - before exercise, the effect of the gas bouncing around inside of you while you move about is going to be very uncomfortable.
posted by softsantear at 7:11 AM on October 4, 2008

I'm actually more concerned with metabolism now that I think about it. Thanks in advance!
posted by ostranenie at 7:11 AM on October 4, 2008

And that metabolism thing smells like pure myth.
posted by softsantear at 7:12 AM on October 4, 2008

I've had extended conversations with several physicians and two nephrologists about carbonic acid and the consensus opinion was that it won't do anything bad to you.
posted by Inspector.Gadget at 7:17 AM on October 4, 2008

This is anecdotal evidence rather than science, but when I was studying at a university in Germany in the mid-1990s, the gym complex had no water fountains and my German fellow students drank bottled fizzy water when they were thirsty. I didn't witness any adverse consequences and I was surrounded by impressive athletes.
posted by sueinnyc at 7:48 AM on October 4, 2008

Carbonic acid is one of the forms that carbon dioxide takes in the blood on its route to diffusing out of the lungs. The carbonic acid from seltzer water is just a small source of hydrogen ions that a healthy body is well prepared to deal with.

The hydrogen ions from the carbonic acid in seltzer water may impact a person slightly by saturating some of the bicarbonate ion (-HCO₃) that act as buffers in their blood that prevent hydrogen ions from lowering their blood pH. They will ironically react to form carbonic acid. Carbonic acid is a weak acid that means that when it is dissolved in water most of it stays in the form of carbonic acid and does not release its hydrogen ion. It's only the hydrogen ion that is important in pH.

The normal molarity of -HCO₃ in the blood is around 24mmol. I weigh 200lbs and according to wikipedia my total body water is 60% of my mass so 200 * 0.60 = 120 lbs / 2.2 lbs per kg = 54.54 kg = 1 liter of water = 1 kg = 55 liters of water. 24mmols/ 1000 = 0.024 mols. 55 liters * 0.024 mols = 1.3 mols of -HCO₃.

This says the pH of soda is between 4.61 and 2.92, so lets go with a pH of 4. 10 ^ -4 = 0.0001 mols of hydrogen ions. 0.0001 * 2 (because I drank 2 liters of soda)= 0.0002 mols of hydrogen ions.

So there are 1.3 mols of bicarbonate ions in my body (assuming that the concentration of bicarbonate ions in my blood is similar to the concentration of bicarbonate ions everywhere else) and the soda has 0.0002 mols of hydrogen ions to eliminate. (Very roughly and skipping a step) 1.3- .0002 = 1.3 Not a very big deal.
posted by 517 at 2:15 PM on October 4, 2008 [1 favorite has favorites]

I pretty much live on seltzer water, but I drink still while I'm working out and the short time in the morning before I get to the gym. Mostly this is because I know the carbonation can create gas and indigestion, but I also find still water far more refreshing when I'm exercising. As for it effecting your metabolism, that sounds like pure bunk to me. Water is water (unless we're talking those "vitamin waters" which are not water in my book). If you don't experience any internal discomfort when you drink seltzer immediately before or during exercising, then I wouldn't worry about it. Oh and obviously I am not a doctor or scientist or any of those fancy pants things. This is just a from personal experience/common sense perspective.
posted by katemcd at 5:24 PM on October 4, 2008

No.
posted by dubitable at 11:14 PM on October 4, 2008

It is NOT good for your workout, but I think you can get used to it, as German soccer players guzzle the stuff before, during, and after games. When we had a bunch of german kids playing on my high school soccer team, they all commented on 1)what the hell is this ice water crap, and 2)where is the seltzer water? Here's a quote from someone else who found the same thing:

"The most humorous (and possibly not too healthy) aspect of the game is that some of the Germans drink as they say "water with gas" (sparkling water) during the game. I was always told to avoid carbonated beverages days before an important tennis meet or race, so I cannot even imagine being an athlete and drinking a carbonated beverage in the middle of a football game. The air in the carbonation distorts the absorption of oxygen to the muscles, which is not good for any physical activity, especially that as intense as football."
http://uscmaymester.blogspot.com/2007/05/american-football-in-munich.html

I think it's OK for the muscles, think about all those great german soccer players. What sucks, I think, is having to burp all the time. It messes with your breathing rhythm during cardio, and is really annoying.
posted by wuzandfuzz at 11:33 AM on October 5, 2008