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  1. #1
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    Water intake in hot (>90 degree) conditions?

    I have always used the 16-24 oz/ hr reccomendation for water intake during a ride. This usually works pretty well for me.

    Today I did 85 miles in 95 degree heat w/ high humidity and just felt thirsty the entire time. I got some ice water about 60 miles in and drank about 20 oz of it and once and felt really bloated and full. It seems that sweet spot is still 20-25 oz/hr even in the heat and I am stuck feeling thirsty the whole time. I dont get it.

    What is everyone elses experience with this issue?

  2. #2
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    In preparation for the 2010 24HRs of Adrenalin World Solo 24HR Champs in Australia, there are a series of articles on diet, nutrition and hydration in the regular newsletters leading up to the champs.

    These newsletters are archived and available here. Editions 7, 8 and 9 contain the best articles. They are written by Jennii English, a sports dietician, who is also the wife of the current World and Australian Solo 24Hr Champ Jason English. Listening to her advice seems to work OK for him

  3. #3
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    Drinking 20oz of ice water in one go while you are riding is always going to be bad however hot it is! I had a similar experience last weekend, 24oz per hour just didn't cut it in hot humid weather. I think it is helpful to pre-hydrate the day before if you know that you are going long the next day, and be sure to drink 24-32oz before you start riding (but not all at once!). Yes, you'll need to pee but that's much less inconvenient than running dry (unless you are racing).

    Increase your fluid intake to 32oz per hour, although this may involve some planning to ensure that you have enough refuelling stops en route. It's going to be a long summer so you will have plenty of time to figure out what works for you.

  4. #4
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    Quote Originally Posted by le Matelot
    In preparation for the 2010 24HRs of Adrenalin World Solo 24HR Champs in Australia, there are a series of articles on diet, nutrition and hydration in the regular newsletters leading up to the champs.

    These newsletters are archived and available here. Editions 7, 8 and 9 contain the best articles. They are written by Jennii English, a sports dietician, who is also the wife of the current World and Australian Solo 24Hr Champ Jason English. Listening to her advice seems to work OK for him
    I don't see a 9th one there...am I missing something?

    Also, anyone tried the weighing before and after method to accurately replace fluid? It makes some sense but I wonder if it is similar to the calorie deficit that develops when riding due to the bodies inability to process more than 300 or so calories or so an hour...

  5. #5
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    I know that I focus on prehydration so that my body cools itself correctly, commonly sipping on 20oz during 10-12 mile rides, anything longer is bad territory for cramping and dehydration so I carry my 50oz. camelback and my caged bottle with something sweet in it (sweet tea mix) to restore some of my glucose and eloctrolytes.

    Hope my exerience helps someone else out there?

  6. #6
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    Did you start the ride fully hydrated?

    You doing the BiciCoop race this weekend?

  7. #7
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    If it's over 90, I try to up my fluid intake by about 6-8 ounces per hour. Simple, but it seems to work for me.
    Whining is not a strategy.

  8. #8
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    My summer riding here in East Texas is in very humid and hot weather. We're talking mid 90's to low 100's and humidity levels of 80-90%. I average just under 2 big bottles per hour. These are road rides of 3-4 hours.
    I got back from a one week trip to Colorado and drank 24-30 oz per hour. Temps were 70-80 and low humidity.

  9. #9
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    Your body can only process about 18 to 24 ounces of water in a hour - the rest will just sit there. There's much you can do to get around that - so dumping water on your head or down your back will go a long way towards keeping you cool - sadly hydration is a delicate science and depends on your body - I know even on the hotest days that I can't drink more than one bottle in an hour. Now - what you put into that bottle is BIG deal and much bigger deal on those hot days - more electrolytes - because you're sweating all the good stuff out. I'm not pro and not very scientific with my approach - I'm sure there is a better way - but I know what works for me and that's the key.
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    Quote Originally Posted by santacruzflyer
    My summer riding here in East Texas is in very humid and hot weather. We're talking mid 90's to low 100's and humidity levels of 80-90%. I average just under 2 big bottles per hour. These are road rides of 3-4 hours.
    I got back from a one week trip to Colorado and drank 24-30 oz per hour. Temps were 70-80 and low humidity.
    i live in dallas and its the same thing. 2 bottles (40 oz) per hour. i weigh before and after to make sure im getting enough.

  11. #11
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    Quote Originally Posted by BDT
    Did you start the ride fully hydrated?

    You doing the BiciCoop race this weekend?
    Probably not...and not sure on the race. Oh yeah, you doin a Fools Gold pre ride Brandon? There is an organized one on the 24th

  12. #12
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    I agree with 24-Solo; in that it's a non-basic science. Everyone I know consumes slightly different amounts of fluids; body weight, the body's plumbing, and what they're wearing all seem to affect one's body's comfort factor.

    Simply put, you need to train enough that you can find what works for you. Keep track of all the variables in a notebook; weather (temp/humidity), what you ate before and after the ride, how much water you consumed before/during/after, what you wore during the ride, and ultimately how you felt immediately and several hours after the ride and into the next day (recovery cycle).

  13. #13
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    Pre-hydrate, and make sure there are electrolytes in that liquid. I made the mistake of water-only prehydration before a hot 6-hour race and suffered through 5 hours of cramps.

    -Ryan

  14. #14
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    Over 100f in the San Diego valleys today; did a 5-hour 90 mile road ride and put some theories to the test, things that I did not do last week when I bonked horribly.

    1. Prehydation : drank over a half gallon of gatorade yesterday, together with my usual "too much" coffee.
    2. Four endurolytes and 32oz gatorade with breakfast.

    I felt much, much better on the ride today than last Saturday even though the temp was warmer. I made sure, actually forced myself, to drink at least 24oz per hour and took extra endurolytes too, but I did that last week and still felt lousy.

    Conclusion: for me, the pre-hydration thing works. That's science, that is!

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    Cool. So next ride I will try to prehydrate and stay around 25 oz per hour. We shall see.

    Oh yeah, not going to drink 2 cups of coffee before the next hot ride....really doubt that helped.

  16. #16
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    Supposed to consume 5-12oz every 20 minutes. A little at a time is better than a lot at once.
    mountain biking is not a crime, so quit giving me dirty looks before I bunnyhop your car

  17. #17
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    Quote Originally Posted by Johnny K
    I don't see a 9th one there...am I missing something?
    It has only come out in the last couple of days and I suspect it hasn't been added to the archives yet.

  18. #18
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    Fluid replacement guidelines from the American College of Sports Medicine
    You guys will try to hit a target in the dark.... at least read this and will point you in the right direction
    Sweating rates vary incredible from person to person. Learn to weight yourself before and after to have an idea (after substracting fluid consumed and adding amount peed)of your seating rate; then try to match your losses (sometimes is very dificult but attainable)
    Read about osmolality; the more concentrated the solution (over 8% carbs and around 300 mosm/L) that you put in you body the more it takes to abandon your stomach and that its what happens to many of you.
    24 Solo, the body can absorb way more than 24 oz in a hour (depending pace or intensity off course) and pouring water in your head or back might feel goo but does NOTHING to decrease your core temperature which is the point of being properly hydrated (allow your body to transport heat from the core to the skin to release heat through evaporation, radiation, etc)
    http://journals.lww.com/acsm-msse/Fu...cement.22.aspx

  19. #19
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    Quote Originally Posted by BBW
    Fluid replacement guidelines from the American College of Sports Medicine
    You guys will try to hit a target in the dark.... at least read this and will point you in the right direction
    Sweating rates vary incredible from person to person. Learn to weight yourself before and after to have an idea (after substracting fluid consumed and adding amount peed)of your seating rate; then try to match your losses (sometimes is very dificult but attainable)
    Read about osmolality; the more concentrated the solution (over 8% carbs and around 300 mosm/L) that you put in you body the more it takes to abandon your stomach and that its what happens to many of you.
    24 Solo, the body can absorb way more than 24 oz in a hour (depending pace or intensity off course) and pouring water in your head or back might feel goo but does NOTHING to decrease your core temperature which is the point of being properly hydrated (allow your body to transport heat from the core to the skin to release heat through evaporation, radiation, etc)
    http://journals.lww.com/acsm-msse/Fu...cement.22.aspx
    Good article, don't think anybody will read the entire thing though.
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  20. #20
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    All very good points and valid approaches, I would add that proper hydration is the one facet of endurance racing that can and needs to be worked on and off the bike. Staying hydrated all week long goes a long way towards successful races for me. It's taken me a long time to learn the discipline involved in drinking plenty of fluids morning noon and night, at work, at home, out on the town and every other damn place I find myself.

  21. #21
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    Quote Originally Posted by le Matelot
    It has only come out in the last couple of days and I suspect it hasn't been added to the archives yet.
    Give this a try:

    http://archive.constantcontact.com/f...566110802.html

    Shaun

  22. #22
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    Don't forget...drinking plain water is dramatically less effective than drinking water with electrolytes. In an independent clinical (here is the abstract, PM me for the full PDF) study conducted on smokejumper firefighters, those drinking plain water alone needed to drink 74% more water to achieve the same levels of hydration as those drinking water with an electrolyte solution. In some instances, drinking plain water can actually work to towards dehydration by flushing electrolyte minerals out of you body.

  23. #23
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    Quote Originally Posted by Sarah K
    Don't forget...drinking plain water is dramatically less effective than drinking water with electrolytes. In an independent clinical (here is the abstract, PM me for the full PDF) study conducted on smokejumper firefighters, those drinking plain water alone needed to drink 74% more water to achieve the same levels of hydration as those drinking water with an electrolyte solution. In some instances, drinking plain water can actually work to towards dehydration by flushing electrolyte minerals out of you body.
    I agree! Just found that Powerade has more electrolytes than Gatorade 2. Looked at the ingredients and Powerade has way more, Gatorade 2 is just hyped up. Powerade is the real deal, I can feel the difference when I ride especially on the hot days!
    mountain biking is not a crime, so quit giving me dirty looks before I bunnyhop your car

  24. #24
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    Quote Originally Posted by Sarah K
    Don't forget...drinking plain water is dramatically less effective than drinking water with electrolytes. In an independent clinical (here is the abstract, PM me for the full PDF) study conducted on smokejumper firefighters, those drinking plain water alone needed to drink 74% more water to achieve the same levels of hydration as those drinking water with an electrolyte solution. In some instances, drinking plain water can actually work to towards dehydration by flushing electrolyte minerals out of you body.
    I have experienced this first hand.

  25. #25
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    Quote Originally Posted by BBW
    the body can absorb way more than 24 oz in a hour
    http://journals.lww.com/acsm-msse/Fu...cement.22.aspx

    sorry, wrong. maybe you didn't read all of that letter(not a medical journal or clinical study) or comprehend it properly.

    they keep making reference to this report:
    Montain, S. J., S. N. Cheuvront, and M. N. Sawka. Exercise-associated hyponatremia: quantitative analysis for understand the aetiology. Br. J. Sports Med. 40:98-106, 2006.

    here: http://ajol.info/index.php/sasma/art...iew/31915/5931

    which is about as a flawed report clinically as you can get. they got 412 questionnaires(about how they felt) from a amateur mountain bike race. almost hearsay. they never even talked to any one personally or measured anything. also the amount of time spent on the race was shorter than most endurance racing(40-60 miles for three days) and only 1/3 did the last two days.


    the original "letter" goes on to state in their "opinion"(again with no study to back it up) that you must drink the same amount that you lose per hour to make up for loss. says nothing about absorption rate(which "is" limited).

    this will most certainly send most of us every time into hypernatremia. salt/water imbalance and cramp out. many of these reports are written on people "exercising" not at "training/racing" conditions, which are more extreme and different. aerobically and anaerobically.



    agreed that people have vary different sweat rates, but have a more similar absorption rate. the 16oz to 28oz replacement per hour is subjective to that. but if you sweat more then you are not going to replace it faster.
    thus the point of keeping cooler(like pouring water on your head) is a good idea when possible. that would mean less sweat loss and possible keeping the water balance more in check.


    for the most part electrolytes and fluid replacement is trial and error, to each person. there are guidelines that you can start at and go from there. in colder temperatures you are less likely to sweat as much, but racing cyclecross or the occasional mountain bike race in the snow will produce almost as much sweat loss as a warm day.

    gauging will take some time and your body does have some leeway up and down.
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  26. #26
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    Quote Originally Posted by Johnny K
    I have always used the 16-24 oz/ hr reccomendation for water intake during a ride. This usually works pretty well for me.

    Today I did 85 miles in 95 degree heat w/ high humidity and just felt thirsty the entire time. I got some ice water about 60 miles in and drank about 20 oz of it and once and felt really bloated and full. It seems that sweet spot is still 20-25 oz/hr even in the heat and I am stuck feeling thirsty the whole time. I dont get it.

    What is everyone elses experience with this issue?



    i suspect too much caffeine? or prior alcohol the night before? maybe?
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  27. #27
    BBW
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    Quote Originally Posted by OilcanRacer
    sorry, wrong. maybe you didn't read all of that letter(not a medical journal or clinical study) or comprehend it properly.

    they keep making reference to this report:
    Montain, S. J., S. N. Cheuvront, and M. N. Sawka. Exercise-associated hyponatremia: quantitative analysis for understand the aetiology. Br. J. Sports Med. 40:98-106, 2006.

    here: http://ajol.info/index.php/sasma/art...iew/31915/5931

    which is about as a flawed report clinically as you can get. they got 412 questionnaires(about how they felt) from a amateur mountain bike race. almost hearsay. they never even talked to any one personally or measured anything. also the amount of time spent on the race was shorter than most endurance racing(40-60 miles for three days) and only 1/3 did the last two days.


    the original "letter" goes on to state in their "opinion"(again with no study to back it up) that you must drink the same amount that you lose per hour to make up for loss. says nothing about absorption rate(which "is" limited).

    this will most certainly send most of us every time into hypernatremia. salt/water imbalance and cramp out. many of these reports are written on people "exercising" not at "training/racing" conditions, which are more extreme and different. aerobically and anaerobically.



    agreed that people have vary different sweat rates, but have a more similar absorption rate. the 16oz to 28oz replacement per hour is subjective to that. but if you sweat more then you are not going to replace it faster.
    thus the point of keeping cooler(like pouring water on your head) is a good idea when possible. that would mean less sweat loss and possible keeping the water balance more in check.


    for the most part electrolytes and fluid replacement is trial and error, to each person. there are guidelines that you can start at and go from there. in colder temperatures you are less likely to sweat as much, but racing cyclecross or the occasional mountain bike race in the snow will produce almost as much sweat loss as a warm day.

    gauging will take some time and your body does have some leeway up and down.
    I think you are stupid; that is not a "letter" you moron that is the American College of Sports Medicine fluid GUIDELINES and they are THE highest authority in these subjects.
    Theey make reference to hundreds of studies so I have no idea why you read one and extrapolate only that study to all the guideline.


    Hypernatremia while replacing what why loss? again I think you dont know crap about what you are talking about

    [QUOTE][in colder temperatures you are less likely to sweat as much, but racing cyclecross or the occasional mountain bike race in the snow will produce almost as much sweat loss as a warm day/QUOTE] What!! almost as much? do you know the mechanisms that the body uses to release heat? what about radiation? hint: that's why we dont loose as much water (sweat) in cold weather

    Pouring water in your head does NOTHING to decrease your core temperature, the temperature of your forehead has nothing to do with the physiologic process that we need to keep in control for muscle contraction, etc.
    You are one illiterate so please don't make yourself an @ss (more)
    I clearly wont loose my time reading your reply since you are probably a janitor trying to talk about physiology

  28. #28
    BBW
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    Quote Originally Posted by OilcanRacer
    i suspect too much caffeine? or prior alcohol the night before? maybe?
    bwuahahaha nice..... now you make make diagnosis over the computer with no information whatsoever.... you must be a witch

  29. #29
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    Quote Originally Posted by BBW
    bwuahahaha nice..... now you make make diagnosis over the computer with no information whatsoever.... you must be a witch

    Actually, he is right. Beer the night before and coffee morning of the ride. Rode yesterday and had gatorade before instead of coffee. Wayyyy better ride.

  30. #30
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    [QUOTE=BBW]I think you are stupid; that is not a "letter" you moron that is the American College of Sports Medicine fluid GUIDELINES and they are THE highest authority in these subjects.
    Theey make reference to hundreds of studies so I have no idea why you read one and extrapolate only that study to all the guideline.


    Hypernatremia while replacing what why loss? again I think you dont know crap about what you are talking about

    [in colder temperatures you are less likely to sweat as much, but racing cyclecross or the occasional mountain bike race in the snow will produce almost as much sweat loss as a warm day/QUOTE] What!! almost as much? do you know the mechanisms that the body uses to release heat? what about radiation? hint: that's why we dont loose as much water (sweat) in cold weather

    Pouring water in your head does NOTHING to decrease your core temperature, the temperature of your forehead has nothing to do with the physiologic process that we need to keep in control for muscle contraction, etc.
    You are one illiterate so please don't make yourself an @ss (more)
    I clearly wont loose my time reading your reply since you are probably a janitor trying to talk about physiology




    wow smarty pants you are soooo good at insults.......ahhhh you won't even read my reply? i doubt that.

    so here you go.

    regardless of who wrote that "letter" the only part that addressed how much one can drink per hour was the survey i included. you would think with that kind of credibility they would be more careful and not make statements based on whimsical written papers.
    so the hundreds of references are not applicable here.

    even the "highest authority in these subjects" can write a letter that either does not pertain to us or is taken out of context. your statements are still incorrect!!!


    ok BBW........ as far as sweating in cold temperatures we are usually more bundled up(nobody is just in a skinsuit during the winter) add to the fact that our blood is thicker and the body is used to colder temps. yes the body can and will sweat even when its cold out if your exercise level is high enough.

    core temps can be lowered by applying cold to legs and arms(many many written papers on that). they act as radiators for our bodies. applying water to the bodies acts in the same way as sweat. and guess what, you are not losing electrolytes.


    it seems like all the names and insults you so freely throw out are better applied to yourself. in fact your spewage of mis-facts leads us all to believe you are an internet rider and not a real world one at all.

    please go on believing everything your read on the net from the clinical experts without ever even testing or trying any of this for yourself. if you did you would see the errors of your ways.

    insulting people is a insecure attempt at bringing down others to your lower level.
    good day to you.
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  31. #31
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    Quote Originally Posted by Johnny K
    Actually, he is right. Beer the night before and coffee morning of the ride. Rode yesterday and had gatorade before instead of coffee. Wayyyy better ride.

    only asked because many of us have learned that mistake the hard way
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  32. #32
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    I'm in N. Texas and my secret weapon is Pedialyte. Works wonders, seriously.

    Sport drinks give me stomach cramps.

    PS: They sell them in 8 oz singles, when the temps are >100f here I drink roughly
    1 per hour in addition to water. No science involved, just that I stop roughly ever
    hour and drink one at that time. I can cram 1 or 2 along side my camelbak bladder
    to keep them cool
    Nobody cares...........

  33. #33
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    I don't race but I do ride for long periods of time and have found that drinking a 24oz(I believe) gatorade an hr before I ride helps a lot. Then I mix one 50\50 and put it in my bladder to sip as needed. Its been so hot here in South Florida last couple of months that I have had to experiment with a couple of ideas until I did this. I have done it now 4 rides and am very pleased with the results. Less stopping and stronger rides.
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