Sweat Rate and Hydration During Training

Forum guidelines BT super discount
General Discussion Triathlon Talk » Sweat Rate and Hydration During Training Rss Feed  
Moderators: k9car363, alicefoeller Reply
2009-08-11 8:12 AM

User image

Extreme Veteran
417
100100100100
Davidson
Subject: Sweat Rate and Hydration During Training
I am trying to figure out if my hydration while training is adequate.  I have been plagued by muscle cramps at a lot of my events and long training sessions, so recently I have carefully weighed myself before and after long training sessions along with the liquids I consumed to see if I am hydrating adequately.  So far, I have found that my sweat rate on a long ride varies between 42 oz./hour and 48 oz./hour depending on exertion level and ambient temps. 

Before I did the homework of weighing myself and recording the fluids I consumed, I would have never guessed I was losing this much weight in body fluids.  I should add that I never had to urinate during the rides and after I got back home and went to the bathroom, my urine was a bit darker than normal, but not a lot darker than the normal straw color.  For reference, my body weight varies from about 147 to 153 with a moderately low body fat percentage, maybe 8%-10%.  My question is this.  Should I be replacing every oz. of sweat lost with consumption of my drink of choice?  Right now, I am using Infinit that is heavier on the electrolytes than the standard formula.  I have read that your stomach can't absorb more than about 30 oz./hour.  If that is correct, I will be falling behind by 18 oz./hour from the start and on a three hour ride I will have lost 3 1/2 lbs. or about 2.3% of my body weight.

Thanks in advance for advice,

Greg

2009-08-11 2:06 PM
in reply to: #2340788

User image

Sensei
Sin City
Subject: RE: Sweat Rate and Hydration During Training

I'll try to hit a couple key points.

First, cramping is usually more fitness related than hydration and electrolite related.  The more fit you become, the less you should have cramps - drinking more is not typically the cure.

Generaly, you will become dehydrated during a workout and race, the goal is to manage it and not let it impact performance.  That means, don't worry about drink SO much that you don't lose any weight, that probably just won't happen.

Some experts have said that drinking too much is MORE detrimental than not enough.

I think you are on the right step with doing the calculations, but really, it's about testing and experiment.  Practice your hydration and nutrition.  If you feel strong and have a good workout, it sounds like you got it right.  I would worry more about performance than urine color or loss of body weight or how many times you have to pee while training.

Some have a even more simple mantra of "drink when thirsty".

As an example in my training..  I can't ever remember having to go to the bathroom during ANY workout or race up to 7 hours long.  The only time I ever needed to go was during my IM.  I also live in the desert and feel my hydration is pretty good.

2009-08-11 6:58 PM
in reply to: #2341947

User image

Extreme Veteran
417
100100100100
Davidson
Subject: RE: Sweat Rate and Hydration During Training
Aikidoman,
Thanks a lot for the information.  I had pretty much concluded that my cramping issues were a simple lack of fitness, but when I dug into the weight changes that were occurring during my medium intensity rides and runs, I began to think that maybe it WAS dehydration.  Regardless, it probably isn't helping the situation any when combined with my newness to endurance sports.

My main concern was to know if it was necessary to replace everything you lose during a workout.  I generally don't as my post suggested, but I consume a lot of liquids upon my return to the house and I usually get within a pound or two of my pre-workout weight by the time I feel rehydrated.  I guess the rules are different for an IM since you couldn't stand to fall behind a pound and a half per hour.  Do you just go slower and hydrate more?

Thanks again,
Greg
2009-08-11 10:25 PM
in reply to: #2340788

Member
195
100252525
Akron, OH
Subject: RE: Sweat Rate and Hydration During Training
Go to Hammernutrition.com and you can read their 120 some page booklet on fueling for endurance athletes.  It's a good start on hydration, electrolyte replacement, and fueling.  They believe and seem to have pretty good research and evidence that you need to manage your hydration to lose 1-2% of your body weight, lose more and you suffer poor performance, maintain weight or add weight and you risk the same as well as the potential for severe electrolyte abnormalities.  Check it out.
2009-08-11 11:20 PM
in reply to: #2340788

User image

Expert
1139
100010025
Austin
Subject: RE: Sweat Rate and Hydration During Training
I don't have any scientific information to add to this, but I've found that if I don't hydrate the night before a long workout that I start to feel slightly dehydrated towards the end. So I usually try to get down some water the night before I'm getting up for a long one.
2009-08-11 11:23 PM
in reply to: #2343022

User image

Master
1651
10005001002525
Breckenridge, CO
Subject: RE: Sweat Rate and Hydration During Training
dscottmd - 2009-08-11 9:25 PM
Go to Hammernutrition.com and you can read their 120 some page booklet on fueling for endurance athletes.  It's a good start ...


Whoa. Reading 120 pages is a "good start"?

IMO, it ain't that complicated. Cramping is mostly due to a lack of fitness for the distance and/or effort that you're attempting. Learn what the symptoms of dehydration are for you and drink enough to avoid them. And keep in mind that there's a delay in liquid via mouth hydrating your body. I drink quite a lot of hydrating liquid all the time but I try to drink more on the day before a big training day or a long race so I start out well hydrated.

Edited by breckview 2009-08-11 11:27 PM

New Thread
General Discussion Triathlon Talk » Sweat Rate and Hydration During Training Rss Feed