Home General Training Discussions

Best practice for EN guidelines for pre race hyper sodium drink mixes? [GroupMe]

This is another #forumworthy topic from the 24/7 EN Live GroupMe. Initially started by @Robert Sabo , there are contributions from @Sheila Leard @maurice matthews @Shaughn Simmons (aka KMF man) @Ross Randolph and yours truly!!! 🤣

<--------------paste discussion------------------>

Robert Sabo

Is there a best practice for EN guidelines for pre race hyper sodium drink mixes? @Sheila Leard ?

Sheila Leard

https://blog.skratchlabs.com/blog/hyper-hydration This is from Dr.Allen Lim. A good explanation of how to use hyper-hydration and who it's good for. Your question is good timing because I just studied for re-cert for Sports RD. The landscape for sweat testing and hydration is changing. Hyponatremia is more common than not. So much depends on temp of race, altitude, BP, thirst mechanism (age). I'm going back to look at my own blood panels from a CBC and seeing what my baseline blood sodium levels are. Also, can't ignore USG. protocol for prehydration doesn't always call for high sodium intake. Women definitely have different req. different topic but when estrogen is high water goes up potential for hyponatremia goes up. Aren't you glad you're a dude?

Sheila Leard

* meant to say women retain more water with high estrogen.

Moe Money [Ultra]

I used your suggestion to get the hyper hydration since my races and training are in warm weather and I’m a hyper sweat beast @Sheila Leard

KMF

Best approach is to do your sweat test under race conditions via the EN protocol in the wiki. Once you have defined your individual sweat rate under those conditions, no more guessing is needed in terms of dialing in your hourly sodium and hydration requirement. All that is left is to practice and dial in during your long training days when you are simulating race pace.....

Sheila Leard

@Robert Sabo @KMF for the most part that approach works.But - not always for women.

Moe Money [Ultra]

Sheila Leard

@Moe Money [Ultra] Did you use https://www.levelen.com/ ?

Moe Money [Ultra]

Yep twice @Sheila Leard for bike and run

KMF

@Sheila Leard - if a woman does a sweat test is race like conditions and knows how much water and sodium she is losing in those conditions then replaces accordingly, why does it not work?

Robert Sabo

EN sweat test does not test sodium

Rich Stanbaugh

one loses different amounts of sodium depending on heat acclimatization. Unacclimatized person will lose much more sodium in sweat than one that has acclimatized. This is one of that adaptions that takes place when adapting to hot conditions.

Sheila Leard

@KMF what studies are showing is that the sweat testing a woman does needs to mimic where she is in her cycle on race day because of hormones. If a woman is in a high estrogen phase the kidneys don't respond as well to the hormone that says release water. It makes sweat testing tricky. We've always gone off the equation a liter of sweat has 1000 mg sodium. That is a generalization that is hard to apply to a non-muscular or smaller athlete.

Ross Randolph

Are there any heat/humidity adjustment factors for executing sweat test in cool, dry Northern California when training for a hot, humid subtropical race? I’ve read up on the wiki and listened to the podcasts but advice seems to be to test in the conditions you train. If can’t simulate you have to guesstimate. Just curious.

Robert Sabo

Make your testing area hot and muggy. No fans and no ac. Maybe even a little heat. Simulate it the best you can.

Ross Randolph

@Robert Sabo The engineer in me wants to do multiple tests in multiple conditions and do a little linear regression thinking can add or subtract x% water depending on temp/humidity conditions. Keep calories the same and adjust H2O based on sweat loss. Also wondering if sweat loss changes with age or fitness? Probably overthinking it; adding wind makes too many variables. I’m thinking better to err on side of overhydrating and risk having to pee too much versus opposite.

CoachP [10xKONA🏝]

Totally, I did one packet a day for the three days leading up to my race. Usually after my morning Workout. Did not consume any on race morning or race day. For me it replaced the need to have multiple bottles of extra fluid, a.k.a. Gatorade Endurance

CoachP [10xKONA🏝]

I think a bigger lesson learned for me from racing in the heat is that my fluid needs are so high that I can also do a good job of eating all the calories I planned on. This made minimal difference for the bike, but I did have to play things by ear on the run according to my gut. In other words, getting the required fluid in on the bike was critical and an allowed me to be flexible with my run nutrition. I would argue that run pacing is greater than run nutrition with regards to overall success on race day.

Scott Giljum

#knowledgedrop

KMF

Sodium loss is correlated with sweat loss. Once you know your sweat loss / hour, you can then define a eange of sodium grams lost per hour to replace and dial that in over long race rehearsals. If you are female and understand where your cycle is in race date, simply do the test under race conditions during that time in your cycle. Sorry I can't add more experience on that 1 but maybe @Sheila Leard can add her experience there.

I sent my sweat test to a lab 🔬

KMF

Given there is a range, this is where dialing in becomes important during your race rehearsals

KMF

There is an archived post from me in the forums where I give you a formula for how many grams of sodium lost per ounce of sweat per hour within a range based on scientific studies.

KMF

Given I have raced IMCOZ, IMTX, IMFL, and IMAZ with countless race rehearsals done in the TX heat, I have some practice.....

CoachP [10xKONA🏝]

#forumworthy

Sign In or Register to comment.