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Nokomis
05-02-2006, 08:33 AM
Nanci, I'm hoping you'll have more links for me! :D Thanks again for putting up w/ all the questions!

The Nutrition info was great ~ at Ultracycling fueling_for_endurance (http://www.ultracycling.com/nutrition/fueling_for_endurance.html)
and then I read this:
Even if you've never cramped or don't see this as a real issue, there are other problems that arise from electrolyte depletion, problems that will negatively affect your performance. A deficiency in calcium, for example, can lead to achy joints, heart palpitations, nervousness, and hypertension. A deficiency in potassium will manifest itself in muscular fatigue, diminished reflex function, fluctuations in heartbeat, headaches, and edema. The signs of magnesium deficiency include insomnia, chronic fatigue, poor digestion (to the point where the stomach will shut down), and irritability. A lack of manganese can result in excess perspiration, rapid pulse, and hypertension.

There is no sports drink in existence that provides electrolytes in substantial amounts. Electrolyte needs can vary several hundred percent, depending on heat levels, while caloric intake may only fluctuate by 25-50% and fluid intake may only vary 20-30%. This makes sports drinks, with their set amount of electrolytes and calories per serving, incompatible for meeting the unique and individualistic needs of athletes. Effective electrolyte replacement can and should come from a source not tied in with calories.

So - how do I build an appropriate balance? My standard diet is sodium restricted (1500mg day max) - but when it's hot out there or I'm working hard, my sweat is extra salty & I'm craving those Lay's Original. I also know sodium is only part of the equation, but it's the only one that's currently tangible to me. Lhep?

Nanci
05-02-2006, 10:57 AM
I think you should ask your physician if you need to restrict your sodium when you are cycling and expending more.

If you read at the bottom of this snippet from "Drinking Too Much" from the Ultra Marathon Cycling site, you can see how many of X Brand of electrolyte caps equals the sodium in one liter of sweat.


[SIDEBAR: MEASURING SODIUM]
Labeling on US foods (but not supplements) requires that sodium content be expressed as "mg sodium." However, "mg" are unwieldy for describing blood plasma concentration, so "milliequivalent," or "mEq" is used instead. Milliequivalent is a number, like 'dozen.' Twenty three mg of sodium is equivalent to one mEq of sodium. Normal plasma sodium concentration is 135-145 mEq/liter (or 3105 – 3335 mg/liter!). One teaspoon of table salt contains about 100 mEq sodium, 2400 mg sodium, and 6000 mg sodium chloride. The average daily intake of sodium in the US is 150 mEq, corresponding to about 1.5 teaspoons of table salt. The sodium concentration in sweat varies considerably across individuals, but a reasonable average is 50 mEq/liter. Happily, 50 mEq is about 1000 mg or 1g sodium. Thus, you can easily use "mg" to track your sodium intake. When you get to 1000 mg, you're at about 50 mEq. Among supplements marketed as sodium and/or electrolyte supplements, Succeed® has 15 mEq sodium/capsule, Thermotabs® have 8 mEq sodium/tablet, and Endurolytes® have 2 mEq sodium/capsule. Thus, 3 Succeed®, 6 Thermotabs® or 25 Endurolytes® capsules have the approximate sodium equivalent of an average liter of sweat.

Nanci
05-02-2006, 11:04 AM
http://tinyurl.com/gahxv

This is too much for me to try to paraphrase- basically you weigh yourself, ride for x amount of hours, keep track of how much you drank, weigh yourself when done. How much weight you lost (the longer ride, the better) x 15.2 is your fluid deficit in ounces. Then you subtract your deficit from your total fluid consumption, and then divide by how many hours you rode, and you get your rate of fluid loss per hour. Once you know that, and you know sweat and urine have about 50 meq of sodium per liter, or about 1000 mg per quart, you can replace what you are losing!

Dianyla
05-02-2006, 11:11 AM
Once you know that, and you know sweat and urine have about 50 meq of sodium per liter, or about 1000 mg per quart, you can replace what you are losing!
I just wanted to add that some people are saltier sweaters than others. Also, individuals who aren't acclimated to hot weather will have saltier sweat than those who are accustomed to it. If you see dried white powdery rings of salt on your clothing after a major sweatfest, this is a big clue. :eek:

SadieKate
05-02-2006, 11:35 AM
If you see dried white powdery rings of salt on your clothing after a major sweatfest, this is a big clue. :eek:Or face.

We judge the heat of the day based on Bubba's level of "crispiness" post ride.

maillotpois
05-02-2006, 11:58 AM
Or face.

We judge the heat of the day based on Bubba's level of "crispiness" post ride.


I thought she was goin' on a trip...? (Safe flight SK).