Nutrition advice - how to avert another Ironman disaster

Hello all- I’m looking for help on figuring out what exactly is going on with my nutrition plan. My stomach has historically been my weak link and I thought I had a good plan heading into racing my first full this fall, but need help. Quick background: 53 years old, didn’t start doing tri’s until I was 36, did my first HIM in about 5:10 which included a flat tire late on the bike. First marathon was at 41 when I ran 3:17 at California International. So decently fast for normal people but obviously nowhere close by slowtwitch standards. Had some injuries which kept me from racing for years, and absolutely have slowed down with age and lack of year-over-year consistent training. But I’ve been healthy the last couple of years and had a consistent build-up to attempting to complete my first Ironman. My last two halves were Santa Cruz in late 2022 and Oregon this year in July, both around 6:00 - Oregon has the short swim but I also had a flat there going over railroad tracks, so I figure it kind of offsets the swim. But my general expectation for a full was to finish in the area of 13 hours, with around a 1:25 swim, 6:15 bike, and 4:45 marathon plus transitions. No real performance goals other than to just enjoy the experience and finish.

After never finding a product I really tolerated that well, after Oregon I started mixing my own nutrition with sugar, table salt, sodium citrate and Gatorade powder for flavoring. I’m 6’0” and race at 180 pounds, which is really thin for me, not a salty sweater but a moderately heavy one (I prefer to think of it as an “efficient cooler”). For a full Ironman, my plan was to take in four 24-ounce bottles of nutrition along with probably a roughly equal amount of water, continuously sipping an ounce of water, two ounces of nutrition, and another ounce of water roughly every two miles on the bike. This would get around 36 ounces of total fluids per hour, which is on the high end but I had gotten dehydrated previously. Each bottle had one packet of powder, seven tablespoons of sugar, a quarter teaspoon of salt and a half teaspoon of sodium citrate, for 315 calories, 1,000 mg of sodium, and 75 grams of carbs each hour. Training with all my long workouts went much better than it ever had, so I felt really confident going into Ironman California in October.

Unfortunately I had just gotten strep from my daughter the Monday before the race, got diagnosed on Thursday and placed on penicillin by a doctor who apparently did not think it significant to point out any possible problems when I specifically said all I cared about was functioning as well as possible for the race in a few days. I actually felt good (my strep wasn’t that bad and I wouldn’t have gone to the doctor except my daughter’s was much worse and she had to go in) and am not used to antibiotics, so didn’t really think much about the effects. Swim was great, first 80 miles on the bike or so were great, but then stomach clamped down and couldn’t take in any more nutrition. I was mildly/moderately nauseous but never threw up or really had to, but couldn’t ride comfortably in the aero position given the stomach pain – just a moderate squeezing feeling like I would throw up anything else I put down – so the last 30 of the bike were not fun, and by the time I finished, wasn’t sure I could run a mile. Slow jogged around 6 miles, then had to walk for a mile and got more nauseous and light-headed and had chills. Got to medical and they checked my blood oxygen which was 86, then checked again a few minutes later and it was 82. Couldn’t stop teeth-chattering chills and after about 20 minutes just sitting there, I made the decision to stop. Annoyingly (but helpfully for next time) I felt really pretty fine around an hour later.

Given how well training had gone on all my long rides/runs, and talking with my coach afterward, it seemed logical that the antibiotics not letting me digest my nutrition or water properly were a big reason for the breakdown. After a couple of days, I signed up for Arizona hoping to capitalize on the training I had done and be healthy this time.

For whatever reason, Arizona was worse, and my stomach started rebelling only around 40 miles into the bike. I had to stop consuming my bottle nutrition soon after and by the time I rolled up to T2 in 6:42, I had only taken in around 1.5 bottles instead of 4. I did eat around 6 half-bananas on the bike trying to push down the nausea. Felt like absolute garbage going into T2 but wasn’t having uncontrollable chills at least, like at California, so started out just thinking I would try to walk the marathon. For the first hour and 15 minutes, that’s all I could do, but then my stomach relaxed and I was able to run miles 4-13. Stomach then reared up again and I had to walk four, got to run three, then walked until a mile before the finish and was able to run the last mile. Each aid station was an exercise in minimalism, getting by mostly on a few sips of broth and a few sips of water, although there was a nutri-grain bar, a couple things of chips, and a few banana halves in there as well, along with a few sips of coke here and there as well. I ended up running a total of 13 and walking 13, took 6:16 to do the marathon and finished in 14:56, nearly two hours over my race goal. (But ecstatic to finish nonetheless.)

Based on what I thought I would have needed to keep going, I was shocked at being able to continue (in such limited fashion as it was) on so few calories. And looking back, I think once I got on the bike, the problem may have been simply pouring in too much too fast, although I thought my targets were solid and my training supported my ability to handle them.

I know a common major problem leading to how I felt could be over-exertion given current fitness, but don’t feel like that was the case here. I feel like it’s more specifically something I’ve messed up either in my calculations of proper targets of what I need to take in, a proper balance of nutrition/hydration, or something else. If anything, given my goal just to enjoy the long day and the excitement of becoming an Ironman, I was focused on not going too hard and ensuring I could comfortably finish. I was doing around 150 watts on the bike which felt easily sustainable for 6 hours. And when I ran, if my stomach would let me, the legs were good, I was shocked at how good it felt just getting to run those nine in a row, before my stomach shut me down again around the halfway point. Talked to several people who had overbiked and were paying for it on the walk/run, but that wasn’t me.

Anyway, would love to hear what any nutritionists or just experienced full-distance racers think and how they would recommend changing my approach, if I just need to lower my targets of calories/fluids/other or what exactly. It was amazing to finish and I honestly look at my time as a badge of honor of how deep I dug, refusing to quit despite feeling like garbage for like 10 hours out there, but I’d love to actually be able to have exhaustion be my limiter next time and not my gut. Thanks for any thoughts!

It doesn’t really make sense that in a race you would have problems with nutrition, but with long swims and long bikes, you don’t

How much power were you putting out on the bike in the race?

How much power do you put put on your long rides? And how long are your rides?

Any swim/bike bricks in practice?

I’m intrigued in how this thread goes. First IM was 2005 in Austria and I carried all my own nutrition entire day apart from plain water. Was a mission but went perfectly and sub 12 which was well ahead of coached target.

Carry on and last few years I’ve been in way way better shape. And been very precise with nutrition in training and racing, but it’s gone very very badly wrong. Last time it went wrong on the bike, despite being identical from training. To give context, I’d regularly do a 90 min squad ocean swim then head off for a 150k bike in the months before race. I used alarms in training and racing to have the same food / gels / drink. Same power, same conditions (or at least race day was within the range of training rides.)
I’d also done a couple of on course full distance rides with 10km runs before hand with no issues.

So I’m now at the point that it’s stress (mental) related. When I was just aiming to finish with no pressure all went well. But when I have expectations to be at the pointy end it all goes to crap.
Literally.

About 150 watts on the first half then around 135-140 to even lower as I faded. Several 4-5+ hour rides going up to 100 miles, and training was very consistent dialed in at those watts. I only did one swim bike brick which went fine. And I agree it doesn’t make sense if it was going ok in training…! Grilled chicken and white rice for lunch/dinner day before, had one ensure plus, 2 nutri grain bars and a banana for breakfast around three hours before race. And on bike I stopped at miles 56 and 104 to pee, hydration seemed normal to a bit low perhaps.

My easy answer is : “test, test, test“. Racing is simply a long training day and if you have properly tested you do not have problems on race day.

Most people do not test properly. Exact same pre-workout nutrition, workout intensity and nutrition. It is impossible for us not to work the same on race day as it does in training.

Personally, I think your mixtures are too strong, the wrong combination, and way too much fluid. I rarely have to stop and pee during an Ironman race, but of course I have tested tested tested. I personally find it a little hard to believe that at your size you can actually handle and process that much fluid per hour. I also think you have too much sodium in there. I believe research would show that you don’t need that. . If those two things are out of whack, it throws off your whole day.

In my 42 years of Triathlon, including 32 Iron Man finishes, I have found that simplifying nutrition works better than complicating. I always study what is being offered on the course, and then test it according to my fluids and calorie needs. That has never really failed.

Many people also base their intake on their outtake. Although certainly there is something to learn from that, the question is what can you uptake. For example, you are really sabotaging yourself if you are intaking 36 ounces per hour and you can only uptake 28. The same goes for calories, and also electrolytes/nutrients.

This really does not have to be that hard. Test test test at race intensity, and then make your race a long training day.

Wishing you the best and hope you get things figured out.

I came off the bike in AZ with a stomach that wasn’t responding properly. It felt all bloaty and felt like things that weren’t moving through the system.

Usually my stomach is pretty good, and I follow the same proven intake formula for each long ride, but I believe I made two errors:
-I pushed too hard on loop 1. The first thing out bodies do when stressed is to divert blood from digestion to heart/lungs.
-I mixed too much concentrate loop 1. I run a concentrate behind the saddle and mix with water during races. Usually at home I just mix 200 cals per bottle, but in a race I put how much I need for the whole race in the concentrate bottle and then eyeball it for how much I need at each aid station. The system works for a 70.3 where there’s 3 aid stations but eyeballing for 8 aid stations in this race didn’t work.

Nutrition is one of the things I’m going to look at for my next IM but I’m going to test out going more liquid for my calories. I usually run a combo of Tailwind, Maurten and Clif Bloks but I’m thinking it’s time to retire the Bloks in favour of more Maurten.

Sounds like you answered your question. Something I have been stressing to a friend who has IM nutrition issues is that you don’t “eyeball” or go by “feel.” If properly tested, it is simple mathematics and you just follow the math. Now, of course, there will also be good days and bad days, but that is sort of the way it goes. Good luck on getting it sorted out.

Thanks for the thorough response, much appreciated- I think the most confounding thing is how my training WAS so similar and locked in and repeatable and went fine, and then had first the bad day on antibiotics which I could excuse if that were in fancy the issue. But then the bad day when I thought I should have been fine in Arizona. Still can’t explain that but possibly something to do with having a long swim before, and my race results simply are what they are - something simply was not working at ALL. But I think your conclusions are very much in line with my suspicions- that my targets are just off a bit and I was trying to put too much of everything into my stomach in a mistaken attempt to replenish more than my body could actually absorb, particularly as my effort was NOT too hard and the weather was for the most part quite comfortable as opposed to a hotter day with more sweat loss. Do you have a general target for calories and sodium per hour?

-I mixed too much concentrate loop 1. I run a concentrate behind the saddle and mix with water during races. Usually at home I just mix 200 cals per bottle, but in a race I put how much I need for the whole race in the concentrate bottle and then eyeball it for how much I need at each aid station. The system works for a 70.3 where there’s 3 aid stations but eyeballing for 8 aid stations in this race didn’t work.

Despite my above fails (2/7 IM, rest been perfect nutrition-wise) then I’m very geeky about the concentrate. My ‘solution’ is to use a clear/semiclear bottle for the concentrate and then mark with a pen on the side the ‘servings’ so that I am fairly accurate. Note that to do this I fill the bottle up with water, invert it, then squeeze the dose into a measuring cup/jug, add a line, then repeat until done. This is to avoid the issue of the ‘air’ in the cap space being measured when you invert the bottle to squeeze. Ie don’t mark the bottle by standing it on a bench and pouring in 200ml at a time (or whatever) as you fill it.

For sure your first race was probably due to the antibiotics. The second race I think you were just trying to do too much.

My general target is 24 ounces of fluids per hour 300 cal per hour, And ~500 mg of sodium. I have experimented with moving my fluids and calories up and down based on temperature and conditions. However, those are only slight modifications. Note that between our one and four on the bike I am closer to three 50–400 cal, but then bring it back down in the closing hour and a half to the 300 range to settle for the run. However, all of this has been tested and verified.

Again, figure it out and then it is simply a math equation that you have to stick to very diligently.

Thanks for the thorough response, much appreciated- I think the most confounding thing is how my training WAS so similar and locked in and repeatable and went fine, and then had first the bad day on antibiotics which I could excuse if that were in fancy the issue. But then the bad day when I thought I should have been fine in Arizona. Still can’t explain that but possibly something to do with having a long swim before, and my race results simply are what they are - something simply was not working at ALL. But I think your conclusions are very much in line with my suspicions- that my targets are just off a bit and I was trying to put too much of everything into my stomach in a mistaken attempt to replenish more than my body could actually absorb, particularly as my effort was NOT too hard and the weather was for the most part quite comfortable as opposed to a hotter day with more sweat loss. Do you have a general target for calories and sodium per hour?

I highly recommend looking at the app by the name Saturday

It makes nutrition so easy

A Dr here in the forum created it

That’s actually exactly how I saw the idea to start mixing my own nutrition with those ingredients I mentioned.

Questions that might lead us to an answer: (apologies if I missed these answers somewhere)
Was breakfast different or differently timed on race day? If so, how?Was pre-race (from waking to race start) hydration or hydration timing different from training days? If so, by how much? What did they each look like?Did you use Saturday’s triathlon activity type for planning this? If so, how did your gut feel after consuming the pre-swim amounts? How’d it feel on the swim?If not using Saturday, what did you do for your pre-swim / warm-up hydration and fueling?Any fuel or hydration consumed on the swim? Sometimes the swim leg can be quite dehydrating for folks and gut tolerance on the bike will be substantially limited compared to in training. If that’s the case, *and * you slightly over-push the power on the first half of the bike leg, you can end up having earlier gut issues than you’d expect based on bike training gut tolerance results.