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Please Help Me with this Sweat Test result

 I'm just now taking the time to do the Sweat Test.  Don't hate.

5.5 weeks out from IMFL.  Have dialed in the nutrition webinar but I've neglected this test.  It may be a key find for me.  I've always been a heavy sweater but I didn't know that it was this much.  I had no idea.  And, it would be way cool if this could help me get faster/stronger on race days.

 

prescribed 2.5 hrs run.  Hot Fall day.  83 degrees, rolling hills.  tried holding z1/LRP  minus a few seconds but ignored the needed slowing effect of the hills.  That probably means I was running a little harder than was prescribed.

Original plan was 1  24oz. bottle Perform/hour, 1 PowerBar Gel/hr, and 1Saltstick Cap/hr.  Used a FuelBelt.  However, gel#2 fell out of the fuelbelt never to be seen again.

starting weight - 164.5

ending weight- 156.0

first few miles were easy/steady, then the next 10-11 were just a bit quicker but manageable, and the last 1.5 were death march stuff.

 

Based on the calcs from the wiki, my suggested fluid replacement should be between 76 and 105 ounces!!!!!!!!!!

1.  How in the world am I to pull that off?

Note:  I will do this test several more times in the next 2 weeks to dial this in.

2.  I can almost understand 2-3 bottles on the bike/hour.  Definitely 2 is more realistic than 3.  Anyways, I can see stomaching that much while on the bike if intensity stays VERY low.  BUT, there's NO WAY anybody drinks that much fluid on the run.  So, how do you do it?  How do you recommend I approach this?

I'm not freaking, yet.  I take a lesson from every workout, good or bad.  I have about 3 weeks to devote to this.  Give me your tips, let me try it out, tweak it a bit, and I'll keep you updated cuz this may be my most eye opening realization since I joined the team.

 

 

Comments

  • I would try the QT2 or Nuun sweat test instead of the one you did. When you get the core race plan that is what they have you do. Basically it is a one hour test on the bike or run. But go to the QT2 website and go to their calculators section to get your zone 2 numbers as mine were different on their website then they are here at EN; read higher. First time I did the test I simply didn't go hard enough and lost almost no weight.
    From Nuun website:
    Calculating Your Sweat Rate

    Average sweat rate is typically 1 – 1.5L of fluid per hour (32-48oz), and 500 – 1,500mg of sodium per hour, however your personal sweat rate will depend on several factors such the environmental conditions (temperature, humidity); genetics, and the athletic conditioning of the athlete.

    Your sweat rate can be determined by a simple “sweat test”:

    Take body weight before a one-hour moderate intensity bike or run.
    Record the amount of liquid consumed during workout, and weigh yourself again after the workout.
    Calculate the weight change and remember to add in the amount of liquid consumed during the workout.
    Every pound lost during your workout is equal to 16 oz of fluid.

    Most people’s sweat contains about 500mg of sodium per 16oz. Very salty sweaters can have up to 1000mg or 1500mg per 16oz of sweat. As a very general rule of thumb, during long walking or running events, you should pee a minimum of every 2.5 hours to ensure you are staying hydrated.

    Also note that on hotter days you should pre-load so go heavier in the beginning 3 bottles instead of two for example - then taper off as you start to pee.
  • kudos to you for getting this done (almost negated by you promoting the post...) image

    x2 what Attila said, but also remember that we strive to replace all fluids 100% on the BIKE but we drink what we can on the RUN. So if you are a sweater, you are looking at more 3 than 2 bottles on the bike per hour.

    Your body can't handle all that fluid on the run, but you can be 100% coming off the bike. Remember you won't also be at 164.5 when you get off the bike....so you will lose a few lbs but not that much. At the very least you can get in 4oz (one paper cup) of fluid an aid station, maybe two....at 10' miles that's 24 to 48oz...which is pretty good...keep us posted!
  • Thanks Guys.



    @AM - I'll give the other test a try just to see if it's still in the same ballpark.



    @P - so, it sounds like I'm basically downing a bottle and reloading thru every bike aid station. Aggressive, but I can do it. And, I understand your point about bike vs run. 5 weeks of experimenting left to do.

  • @Chris - in high humidity, I am up there with you. You can work to increase your fluid intake on the run, but it is more difficult when you are 'self-supported'. Do you run w/ a FuelBelt? I hope so. In addition to that, you can also carry 1 or 2 of the 16.9 oz water bottles and discard (to be picked up when run is complete) as you go. If you run a one-hour loop, that will get you 28oz on your FuelBelt and 34oz carried, for a total of 62oz per hour. It seems like a lot, but if it is hot and/or humid, it can be done. Especially so if you are running at EP.
  • Right Joe. I do use a FuelBelt. But, either the velcro is crapping out or I've lost alot of weight. This last run, it kept trying to fall down around my hammy's. It drove me nuts. You're right about the 'self-supported' nuances. On race day, if I'm downing 4oz at every aid station, I should be alright. But, these run 'practices' can be a little trickier with the logistics. Doesn't matter, tho. I have to get this. All the intervals in the world won't help me if I'm sabotaging myself with the fluid stuff.

    BTW, will I see you at the Six Gap ride this Sunday?
  •  Chris obviously what everyone else has said is awesome. My only offer is to try a lighter solution such as Nuun v. Perform. Also what Coach P said is so true, drink on the bike. On your stand alone long runs, pre plant bottles, do loops or have someone come out and give you 4 oz every 2 miles or so. You cold even ask them to hold it out as at an aid station. My husband did this for me on the bike so I could practice hand ups. The biggest thing I also do is pre load before a long run. I have about 24 oz the 30 mins before the run to start out "full" and drink from my fuel belt every half mile ( a sip). You will get this, don't "sweat" it 

  • Thx Deb. good ideas. Tho I don't have enough SAU's saved up to get Sheri out there handing me dixie cups! I'm afraid of that payback. I'll probably do most of the remaining runs on a 1.2 mile loop that we have in the 'hood. I'll stash a cooler to reload Fuelbelt when needed.
  • Chris x2 on what everybody said . Specially coach P about coming off the bike 100% and drinking what you can on the run.

    Having said that, IMO the most important sweat test you can do is on the bike(outside not on a trainer) trying to replicate the course, temps , humidity , and intensity of race day. It doesnt make any sense to do the test at IF .85 if you plan to ride .70, nor does it make any sense to do a run sweat test to figure out how much you need on the bike!
  • Makes good sense, Tim.

    I did plan on getting a variety of tests done and see how they varied, bike vs run, etc.

    Unfortunately, my next day to stress the system will be Sunday, 6-7 hr ride thru the mountains of N Ga. I'll still weigh in and weigh out, sans nudity. Probably light/dry running shorts will be used on the scale. And, I'm going to try to stick close to my race plan so that I don't start bogging the system down with cookies and bagels at the rest stops. This should allow me to do the math easier, too.

    Thanks
  • Test #2 this morning....



    off the reservation for this weekend. big 100 mile ride in the mountains tomorrow. So, I did a pre bike 45'' run followed by an ez 1' bike with the S2 just to make sure everything is shifting well (think testing the Granny gears)



    But, I'm still sweat testing on both of these days...



    So.... today,



    6am, 68*, some LRP and HMP running, then a really ez bike, sweat test results---> 55-80 oz/hr



    big difference from Thursday  (calculated 70-100 oz/hr)  but effort and temp were very different, too.



    will continue to collect data and find a happy medium.



    feedback is appreciated.

  • Chris that is a big difference. Kind of my point to sweat test on the bike outside in similar race and effort conditions. I believe too many people test via run , bike trainer, or at too high of an intensity on the bike , to calculate an IM bike ride sweat loss.

    FWIW @ IMFL your first hour on the bike could very well be in the low 50's , the second hour high 50's to low 60's , then into the 70's. That is quite a variable right there!

    Keep collecting your data its not rocket science just make sure its comparable. Enjoy that century!
  • So, Tim,

    Let's say I collect test results from 5-10 different workouts. Sounds like you're suggesting that I take the days like the Sunday ABP rides, or definitely the next RR, as key Sweat Test Days since they will mimic race day efforts.

    I think you may be right. I'm still going to collect several days worth, but I will look at those SimilarRaceEffort days a little closer.

    thanks.
  • @ Chris

    For several years now, even before EN on any and all my long runs > 2hr, I'd calc my sweat rate and depletion.

    Weigh out, weigh in, what did I drink, temp, humidity, intensity. Never cataloged any but just mentally go over the details. End result is I have a good idea what long runs require at temps from the mid 30's to upper 80's.

    It's a simple exercise to do and take no time at all. You'll be better informed and have better control of how your body is functioning in any circumstance.
  • @Chris.... I think an ABP sweat test done at IF .85 would be a good indicator for a HIM.... NOT an IM!..... A RR done at IM pace would be more appropriate for your IMFL race...

    The problem with long sweat tests is .... Tracking and caclulating urination into the sweat equation.... My theory is an hour or two at planned intesity with no pee's between your weigh in's will give you a much better estimate since you can keep track of every ounce you put in but not out unless you collect it!!!

    Maybe someone else can chime in on the length of tests? X2 on what Steve said just keeping track of multiple workouts , temps, etc.
  • Hearing you guys.

    Thanks.
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