Sounds to me like you have already answered your own question.

Calories in that make your stomach feel like crap do not help. A lot of people do an IM bike at or around 300/ hr and do just fine on the run. I have had trouble in the past with fullness around 350/hr. Tomorrow I will IM on 260/hr. With a ton of training, at 260, I have determined that to be the max intake for me on the bike.

One of the old classic recommendations that seems to work quite well for many folks is to consume 1 gram of carbohydrate per kilogram of body weight per hour. You weigh 207/2.2= 94 kg 94kg X 4 Calories per gram of CHO = 376 Calories per hour.
You may be fine at the 425/ hour rate but 500+ is way what I'd recommend.

Hugh

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Genetics load the gun, lifestyle pulls the trigger.

Same thing happened to me. I had to cut some calories to get the stomach to settle down on my next few bike rides.

I tend to be in the 300 calorie range now. Unless my body is craving it then I listen to it.

hope you got a 6 pack of abs showing , otherwise taking in too much... a bigger dinner the night before will require less intake during the ride. For an 140.6 I took 6-7 100 cal gels and a 300 cal power bar during the whole race. - had the fastest run split overall ;)

Way too many calories. You averaged ~18mph. On a road bike that's what, 170 watts? No way you're burning 500 calories an hour. Drop it down to 300 an hour and see how you feel.

I'm not too efficient (mostly fast glycolytic) and try to take in ~400 an hour at 200 watts average. What I've found though, is that when I start out, the first 14 miles or so, I'm eating a lot but my body isn't quite warmed up yet. I'm not breaking down much glycogen and end up with an upset stomach due to all of the sugar.

If I cut the intake back during the first hour or so and then ramp up upon mile 20+ I end up feeling better during the entire ride.

Also, mix up the calories. I bring fig bars or clif bars now to supplement the majority of the calories and then use gels or chomps when I'm pushing hard and need the calories quickly.

Take in the 425 calories an hour or less bro on the bike, if I were you I would go down to the 300 range. You don't need that many calories trust me, once you start over feeding or messing with your stomach on an IM your gonna be back here asking why you bonked.

Moderate calories on the bike and take in small quantities spread out on the run. Your over thinking it

Search here for IM nutrition on here plenty of threads

This is a useful site to assessing calorie intake and give you a ballpark idea of a useable range.

http://www.graemestewart.com/...utrition-calculator/

If you were putting out 170w then it recommends a max intake of 386cals/hour. You pushed in much more than this, so not surprising that it was still sloshing around when you got onto the run.

^^^^^^very cool. Thx

I would ditch the bonk breakers, no need to compliacate things with that much fat and protein. See If you can go 100% liquid (practice in training).

Also 8 bottles total? Likely fine in training but you may need more for the race.

Also practice under load (race specific intensity) are you planning to go Z or L2 in the race?

Everyone is different, we have some small females 120-125lbs at 350/ hour on the bike. Myself at about 425 bike and 275-300 run.

Maurice

Yesterday I rode 100 miles (5:45 total time and consumed about 120 cals per hour :-/

Today rode again for a total of 70 in 4:30 with 1 gel.

I find the fitter I get the less calories my body usually requires. By the time IM rolls around I usually take in 3-400 calories an hour.
It is easier to take in liquid calories without feeling bloated.

Interesting that I'm on the very low end of their recommendations, I honestly thought I was at the higher end with 2 GU's per hour plus some Gatorade/Infinit

I'm going to need to experiment with a little more and see how it goes.

jaretj

I've been told I have a stomach like Will Ferrell so no abs for me. I'll dial it back to no more than 400-425. I'm not using power so I don't think the formula will work for me. Using HR but I think it sucks. Yes, basically have been rolling with about 8 25 oz. bottles for my 100 mile rides. Too little??

Also, when it comes to bonking is it primarily a lack of calorie intake or fluid intake? Or a combo of both?

You're a lot bigger than I am but I would think that 400-425 would be on the upper end of what you need.

Personally I limit what I drink near the end of a bike ride so my stomach is not full when I start the run. In fact I like it near empty so I drink early.

I find that the fluid will slosh around in my stomach and whatever I eat afterwards won't be absorbed. That's what happened to me at my last IM but that was some time ago.

Also, I race HIM so my intensity is a little bit higher than if I was participating in an IM

Bonking (as used in this context) is from a lack of calories, when I bonk I normally have to sit down, eat something and let the hot flashes go by.

jaretj

I'm a bigger athlete. My abs are still visible from my power lifting years ;). I find most calculators are either intended for smaller people and use the same metric for somebody bigger than somebody smaller and doesn't seem to work at all. I did my first three half ironmans and my ironman on the 300 calculation given to me by several "experts" and calculators like this. This was despite the fact that when taking a third of my calorie count in an hour puts me at almost 400 and I ran out of fuel each run. I would get farther each race, but still. Some say it was fitness, and that certainly played a role, but I was definitely out of fuel. My last HIM race I wrote off since I moved cross country and decided to use it as a nutrition experiment. I went 400 an hour. Ran the whole half marathon (walking through transitions). Despite ramping up my training in the last month, I was just 15 minutes short of my PR, which was all bike (rode my road bike). I also felt great after that race and drove 4 hours back to the town my flight was out of the next morning.

So don't over thinking it. Frankly, I wish I had got some of the advice I saw in this thread in my first race. Sounds like 400 might work for you. If you know what doesn't work dial back, if you know what does work dial up. Find that sweet spot somewhere in between.

On another note, I followed 300 cals in my first and only ironman. When I got off the bike, I couldn't run more than 50 yards without leg muscles failing. Given that I had PF pop up the week before, I figured it would keep me in check and I would walk the marathon. Funny thing, I ramped up the calories for the first 3 miles and was able to run the next four at a good pace before the pain in my foot from the PF became unbearable to even walk anymore. Though anecdotal, this is why I think it was fueling more than fitness. If it was muscle fatigue, I don't think it would have rebound after 1 hour of walking and a couple bags of pretzels and Gatorade.

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"In the world I see you are stalking elk through the damp canyon forests around the ruins of Rockefeller Center. You'll wear leather clothes that will last you the rest of your life. You'll climb the wrist-thick kudzu vines that wrap the Sears Towers. And when you look down, you'll see tiny figures pounding corn, laying stripes of venison on the empty car pool lane of some abandoned superhighway." T Durden

Realistically how high do you think you could go?
Do you think that you could do more if for some reason you fell behind on your nutrition? Like if you dropped an 800 calorie bottle or something like that?

I ask cuz I have many friends that are bigger than I am and I'd like to help them.

jaretj

9x out of 10 "bonking" comes from under training and over extentending oneself during a race. Fueling takes a part of the equation, but usually small with AG.

On your next 5hour bike then run try the 400calories on the bike an hour. Your obviously not looking to place in an AG with your weight but you just want to have enough fuel in your stomach to get to the next leg with energy not a full stomach. If you want to hit Old Country Buffett afterwards go for it.

And the liquid just take enough on your bike (not including fuel) for the next fuel station, during an IM I always buzz each fuel station for Gatorade or water or both, stash it on your bike and your body will tell you want you need.

With those hills at IMLP and your weight no offense but just pace yourself on the bike, especially the first loop cause that second loop will wear you down. It's gonna be a long day just have fun

How often do you train taking in that many calories? Your digestive system adapts like your muscles. If you do most of your workouts with a little fuel and then your one long ride with your race plan that is not enough. Make sure to do it a few times a week.

There are pros that do 600 calories an hour but they train daily to do so. At your size use one of the calculators and go from there. Play with the fuel plan too as it should reflect your intensity. The plan of an 8 hour finisher vs 16 hour finisher should not be that similar.

Bonking is from not fueling adequately for the level of exercise you are performing.

That is why I had bonking in " ", most people AG think they bonked or couldn't continue due to lack of fueling but 9/10 its just from fatigue and not being trained enough.

I would just ditch the bonk breaker and keep Infinit + GU.

I think I know what you mean now.

800? No way. But I have had solid long training rides or uns after eating a solid breakfast (within an hour of ride) and then consuming 300-400 an hour. But I would put the pretzels and Gatorade I ate within that hour at 500-600. I couldn't possibly maintain that during a run, but it definitely helped get me going again.

The point I'm making is these calculators often put the higher scale for people at 120-150 lbs at around 200-225 calories yet somebody who ways 200 - 220 consuming 275 - 300? And in the words of two nutritionist I talked to "nobody can consume more than 300 an hour without issues". I'm just saying that the max is BS. I think an elite athlete at any weight consumes a lot less. I think most sports nutritionist don't have to deal with bigger people racing long course races. The best advice I got was from a take 1/3 of your average calories burned for an activity and that is your baseline. Adjust accordingly. As for refueling, you still have to be mindful of what you can process. IN my case with the ironman, I was walking and eating, so I wasn't burning anywhere near the calories I would have running in the same timeframe, so excess calories that were safe stomach wise were going right into the blood and muscles.

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"In the world I see you are stalking elk through the damp canyon forests around the ruins of Rockefeller Center. You'll wear leather clothes that will last you the rest of your life. You'll climb the wrist-thick kudzu vines that wrap the Sears Towers. And when you look down, you'll see tiny figures pounding corn, laying stripes of venison on the empty car pool lane of some abandoned superhighway." T Durden

I have run two hours after a big Italian dinner (acidic) more than a few times. Lets just say that is the closes to stomach issues I ever had. On one occasion some came up, but I kept going.

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"In the world I see you are stalking elk through the damp canyon forests around the ruins of Rockefeller Center. You'll wear leather clothes that will last you the rest of your life. You'll climb the wrist-thick kudzu vines that wrap the Sears Towers. And when you look down, you'll see tiny figures pounding corn, laying stripes of venison on the empty car pool lane of some abandoned superhighway." T Durden