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27403 Views 7 Replies Latest reply: Apr 11, 2014 6:46 PM by Moriates
KAmighi Rookie 4 posts since
Apr 5, 2008
Currently Being Moderated

Aug 26, 2013 2:52 PM

Half-Ironman fueling and timing

I am attempting my first half-Ironman in two weeks, and I am, in a word: Terr.I.Fied. That being said, I'm looking for advice, first, on how to feul. How much food/gels/liquids do I need to consume on the ride? I've done one successful brick of a 2-hr. ride followed by a 1-hr. run, and finished most of a water-only bottle and an electrolyte-drink bottle, plus 2 Clif Bloks (my preferred gel) and half a protein bar.  I needed water on my run and should have taken some with me, but that's easy to correct, with water stops along the route. What I'm wondering is if I need to pack like a pb&j to eat (the ride will likely take me 4 hrs). Any advice would be greatly appreciated.

And, about that 4-hr ride: the race site says the bike course closes at noon (with a 7am start). Well, that would be wonderful but it might be difficult for me to be off the bike by then. Does that mean I'll be DNF'd? Do they close the course and consider anyone still out there done and over? Subsequently, the site says the run course closes at 3pm--even more unlikely for me (but not by much I hope ). I just want the finish to count. Will it if it takes me 8 1/2 hrs to do the whole thing? Thanks for any and all advice, courage, support you can give me. A terrible summer (weather, death in family) has put me a bit behind on training but I don't want to give up. Thanks everybody.

  • Julie Ann Hackett Legend 226 posts since
    Nov 20, 2007
    Currently Being Moderated
    1. Aug 28, 2013 10:02 AM (in response to KAmighi)
    Half-Ironman fueling and timing

    For fuel, I wouldn't try anything new on race day.  I would load up your bento box with the blocks and gels that you know work for you and won't upset your stomache.  There's usually water on a bike course of that distance (but check) so you can always refill your bottles if needed.  And you're right, just go with the water they have on course for the run and you should be fine.  I try to eat as much solid food as I need on the bike because my stomache can't handle much food on the run.  There should be some type of fuel on the bike and the run, so check on that and know where it is so you can have a backup plan.


    As for the course closing, it really depends on the permits and the race director.  If your worried about not making the cutoff times I would suggest emailing the race director to find out how they handle it.  Sometimes you can keep going but I know some races they do make you stop and you end up with a DNF.  If they are hard cutoffs and you are worried, just tell yourself this will be a "training race" and pick another half to work toward and look forward to.  Be kind to yourself and do your best - it sounds like you've had a challenging summer.  Kudos to you for pushing through things and heading to the race. Best of luck!

  • BT.ROB Legend 270 posts since
    May 12, 2009
    Currently Being Moderated
    2. Sep 4, 2013 9:33 AM (in response to KAmighi)
    Half-Ironman fueling and timing

    I echo what Julie said about not trying anything new on race day. That being said, fueling is very personal. You should know what works and what doesn't from your training. Your body can only absorb so many calories per hour (200-300) and fluid per hour (20-30 oz). In addition to underfueling (bonking) some athletes take in too much fuel/liquid and have other GI distress. I usually go through a bottle an hour on the bike and take water at each aid station (sipping a bit, swishing some and rinsing my mouth). I'm ok with liquid food and gels, but others like a bit of variety in their mouth. A PB&J is a good choice. I have used Fig Newtons too.


    Good advice from Julie on course closings as well. Some will let you go on "at your own risk" and take your timing chip. At an Iron distance race I did, I had mechanical issues with the bike and came in two hours later than I expected (but within the time cutoff). At that point it became a training run just making sure I hit the time cut-offs and the finish. The goal was to finish anyway so I hit that!


    Good luck and have fun!


  • Billy137 Amateur 14 posts since
    Feb 8, 2012
    Currently Being Moderated
    3. Sep 4, 2013 9:41 AM (in response to KAmighi)
    Half-Ironman fueling and timing

    For fueling, like Julie said don't try anything new on race day.  I know it can be tempting because you are nervous, but don't do it.  I'm guessing the race is this weekend?  Solid food is fin on the bike if you can handle it, I mainly stick with gu's and gels and sometimes the bonk breakers.  I usually can't eat solid food during the race very well, so I don't force it and get my calories elsewhere.  The main thing is to keep taking in something, whether it be a pb&j or a gu.  I did a full Ironman last year and got my fueling down to about every 45 minutes taking a gu or blocks.  It worked very well, I only got drained once on the bike because I was turning against myself.  After that I took a bonk breaker and recovered quickly.  But I wouldn't think of trying solid food on the run.  The bad thing is if you don't get it all down you don't replace what you needed soon enough and will lose the energy.  Stay focused and know that when you are tired or weak, you need to eat and drink. 


    If your event is ran by Ironman they do have set cutoffs and you don't get to finish the race if you don't make it in time.  Some other events are sometimes low key and will blur the lines a bit, but they should have that all set out in a race packet.  Don't sell yourself short.  Don't look at the times and think they aren't possible, look at them and know what you have to do to beat them.  Don't stress yourself out over those things, just stay focused on the task at hand and you'll be fine.  You will probably go through the cut-offs with plenty of time to spare.  And by the way, a finish always counts, even if there's a DNF by your name.  Good luck on your race.

  • notsodeadly Amateur 15 posts since
    Jun 8, 2010
    Currently Being Moderated
    4. Sep 18, 2013 12:02 PM (in response to KAmighi)
    Re: Half-Ironman fueling and timing

    Some of the best advice I have ever got was "any race over 3 hours is all about nutrition"  basically, you have to practice your nutrition before the race...sounds like you have a good start and have learned from your mistakes.  Everyones plan is different...I know people that can do a big race like that with nothing much more than water.  As for me, I lose electrolytes faster than most and need to supplement that with the occasional pickle juice and only drinking gatorade on the course.  My last marathon i ate 10 gels over the 5 hours.  Your boddy can only digest so much food at a time and at a given intensity level.  gels and similar sugar based foods/drinks are the easiest to digest and why you use those in a race.  In order to eat a PB&J during the race, your heart rate has to be below a certain level or else your body wont digest it until after the race.  Sounds like this race wont be a sprint for you and you will be able to keep your HR in check, so I say go for it on the PB&J.  Aim for 200-400 calories per hour...400 on the bike and 200 on the run.  Plus or minus 50-100 calories depending on your size, speed, exhertion level, etc.  the first 2-3 hours will be running off of the supper and breakfast before the race.  As far as the DNF possibility, i like the idea of emailing the race director...some directors will not allow people to continue on the course for safety reason and pre-arranged agreements with local law enforcement/city govt to reopen roads.  Best of luck on the race!  It is an amazing accomplishment and an addicting thing to go long.  Keep it up.

  • Grandgeorge Rookie 2 posts since
    Nov 4, 2007
    Currently Being Moderated
    5. Dec 18, 2013 8:15 PM (in response to KAmighi)
    Half-Ironman fueling and timing

    I'd avoid the PB&J, particularly if you have not tried this in practice.  As you exercise, blood is diverted away from the stomach, slowing digestion.  A large influx of calories is likely to lead to stomach issues.  Typically for a half IM I'll go a little over 300 calories per hour on the bike, and 200 calories per hour on the run.  With your target pace of around 4 hours on the bike, I would think 300 calories per hour would be plenty.  Higher intensities require more consumed carbs for fuel, and adding more calories than you need simply increases the odds of stomach issues.  With less bouncing and generally lower intensities, most people can tolerate more calories on the bike than the run.  I'd stick with you Cliff products that were used in practice.  The partial protein bar is fine on the bike, but again I'd be concerned about something like that sitting I your stomach on the run.   I'd eat two 100 calorie GU gels per hour, and supplement with part of the bar to get close to 300 calories.  Spread your calories out over each hour, so you don't overload your stomach.  I would avoid eating any protein bar in the last half hour of your bike, going GU only after that point, as you don't want it sitting in your gut when you start to run.  I measure my weight before and after exercise to calculate my sweat rate for hydration.  Without knowing your specific rate, I'd guess a minimum of 16 oz per hour on the bike and maximum of 24, depending on temp.  You don't need to replace all your lost water weight, but you want to avoid losing more than around 3 percent body weight.   Typically aid stations are every mile on the run, and drinking 4 oz (Dixie cup) will be fine.  If it is really hot, you may need to add a second cup every other water station on the run.  Make sure you take in some electrolytes on the run as well as on the bike, as being low on electrolytes makes you feel pretty crappy on the run.   I usually use something like salt stick tablets, one every 6 miles at minimum, up to every 3 miles if it is hot and I'm drinking 2 cups at each aid station.  Good luck, and remember to enjoy the experience.

  • quotesfly Rookie 2 posts since
    Dec 18, 2013
    Currently Being Moderated
    6. Dec 19, 2013 3:05 AM (in response to Grandgeorge)
    Half-Ironman fueling and timing

    I would load up your bento box with the blocks and gels that you know work for you and won't upset your stomache.  There's usually water on a bike course of that distance (but check) so you can always refill your bottles if needed.  And you're right, just go with the water they have on course for the run and you should be fine.  I try to eat as much solid food as I need on the bike because my stomache can't handle much food on the run.

    Thanks a lot!

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  • Moriates Legend 292 posts since
    Jul 19, 2008
    Currently Being Moderated
    7. Apr 11, 2014 6:46 PM (in response to KAmighi)
    Half-Ironman fueling and timing

    I believe that the simpler the better.  I like infinit nutrition.  However, you need to figure out what works for your body and at what intensity.



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