Sent to my buddy, who was concerned about his nutrition. My half IM (and some full IM) nutrition plan:
First, congratulations and great job in reaching this point to undertake your first half IM!
Second, here my views on nutrition:
Although I also have tried to add up calories over time at one point, I have found that it is something that is super hard to quantify like that, and I'm not sure it's useful. Race conditions change and so does your body over time.
For instance, I tried to follow similar nutrition plans at Half Vineman and Honu Half but at the Honu Half, it was a lot hotter and my stomach shut down at one point whereby fluid was sloshing around in there. So I had to stop taking in fluid until my stomach calmed down, and also I walked a lot too. A short while later, magically the fluid in my stomach just got absorbed all of a sudden and then I ran to the finish. This has never happened to me at Half Vineman where the temps are different.
As for my body, I have found that over time, I don't need to dump so much nutrition down as my body's natural strength, endurance, and fitness have risen. At one time I would fill up my water bottles with 1.5 scoops of Accelerade and then an extra scoop of Carbo Pro just to top it off. I found out that doing this meant that after a long ride, I would get diarrhea from too many calories going in and my body just not being able to process it, causing stomach problems. So I backed off on this and only use 1 scoop Accelerade for even a tall water bottle and I don't have any problems, AND I'm getting faster AND I'm not bonking either. So overloading on calories obviously wasn't going to make me faster.
Fine tuning your nutrition is something you should be doing during training, so hopefully you've found your plan. DO NOT DEVIATE from your plan no matter what! Everyone says this but we often don't follow our own advice. You could really mess yourself up if you don't. I've seen people throw up on the course and you ask them afterwards what happened and some of the time they deviated from plan! If you don't throw up during training, you'll probably be ok for the race.
I have many more problems with cramping, so I dump in 3 scoops of Endurolyte powder into each tall water bottle, and one scoop into each 10oz Fuel Belt bottle. I also take 3 Saltstick tabs per hour (1 every 20 min), in addition to the electrolytes in my fluids. This I have tested and have shown no negative effects on this, and it seems to help me control my cramping since I sweat a lot AND I'm a weak piece of shit so cramping comes naturally to me.
Here's my nutrition plan for a half IM (note full IM is slightly different):
3 hours before the race start, I eat a hard boiled egg, and 1/4 plain bagel. Then I sit on the toilet and crap out whatever I can (believe me you don't want to take a crap on the course if you can avoid it; plus I've seen racers with brown streaks out their butts on their race shorts because they had to crap and it just started coming out yuck!). I drink down a cup of First Endurance Pre-Race with a carbo drink, usually I just use Endurox recovery drink before the race (as well as after). I also dump a packet of Emergen-C in there too.
Before the swim starts, I take a Powergel (w/ extra sodium).
After the swim before the bike, I put down another Powergel. I get on my bike and ride. For half IM on the bike, I usually use 2 large water bottles with one scoop Accelerade and 3 scoops Endurolyte powder each.
Usually I don't start taking any more down for a while until my body gets accustomed to riding. I find that I really don't need my first nutrition until 45-1 hr in. But i do start taking salt tabs on my 20 min schedule immediately (it's important to not get into an electrolyte deficit early), and sipping fluids about every 15 min. I take a Powergel every 45 min, a Saltstick tab every 20 min, and sip my water bottle to wash down everything. Depending on the air temp, I may sip more or less than every 20 min.
Generally, I go through 2 large water bottles in a half IM. After I finish one, I immediately toss it to increase my aerodynamics.
If my stomach feels too full, I may wait a bit before my next sip or nutrition.
Hopping off the bike, I go into T2. I keep my eye on my watch and keep fueling my Powergels every 45 min, continuing from when I was on the bike. I may grab a cup of gatorade on the way out, as usually there is a nutrition station at T2 exit.
For half IM, I carry 2 10oz Fuel Belt bottles of Accelerade. But I mix it in another small water bottle so I fill the bottle up, and put one scoop in there, and then dump 2 scoops Endurolyte powder in there. Then I squirt it into 2 10oz bottles.
At some point, I may try to do the race without carrying my own fluids, but now I am too paranoid about my electrolyte problems and cramping to trust only what is out there on the course. Also, sometimes even half ironman aid stations will run out and it's nice to have something to sip if you can't get something on the course.
But inevitably, I am supplementing my Fuel Belt fluids with whatever is on the course. If I reach an aid station and I'm about to take a gel, I'll just drink a Gatorade there instead of sipping from my bottles. I am a huge fan of cola so I will definitely drink that over my own fluids, but at most half IMs you won't find cola, only at full IMs.
Still i gel every 45 min, and take Saltstick tabs every 20 min.
This has seemed to work well for me but it was developed very organically and not very scientifically. Still, I have not bonked ever on a race so thats a plus. I have had other problems but never bonked thankfully.
Check out this article:
Feed the Machine, Triathlete Magazine
In looking at what you're doing, the only thing I might change is to eat the powerbar earlier. Digestive systems start working not as well as time goes on, and your body is more able to deal with solid foods earlier in the race than later.
But note that I only eat energy bars during full IM where I usually put down at least 2, sometimes 3 bars in the first 3 hours. My bar of choice is the Balance Bar Yogurt Honey Peanut. It is very plain tasting and easy to chew. I hate Powerbars because they are so chewy and require more water for me to get down. But i have found that half IMs are short enough that you don't need to have solid food and can do well on gels alone. Besides, eating a bar is harder than gels. You have to unwrap them, take a bite, and then put them back somewhere. If you're going to eat an energy bar, I would time it out. I usually take a 1/4 bar bite every 15 min, so by the end of 1 hour it's gone. Sometimes I take smaller bites, so it's gone after 1.25 or 1.5 hours. But i stop when my stomach feels too full.
Important: do not forget to take nutrition down! Keep focused on the race and keep to your schedule of putting down nutrition. The only time to stop a bit is if your stomach starts to hurt, feel too full, or if you feel like throwing up. Back off on the nutrition then and slow down too, until your system returns.
At each aid station on the run, I take from a mouthful of fluid to a full small cup. Then I wash my mouth out with some water because i hate that sticky feeling. Try not to over drink at an aid station. Just take the drink and move on.
One note: slowing down at an aid station means extra time on the race. At IM WA, for the first half, I didn't stop at all and only took fluid from my Fuel Belt. that strategy fell apart later....ha. But I did reach the half way point faster than I ever have on an IM.
Another point about your plan below. If you are going to bike about 3 hours, then if you gel every 45 min, you should take down 4 gels approximately. If you take one every hour, you're going to need 3.
Always take with you one more gel than you think you'll need, both on the bike and run. I've fumbled gels before on the bike due to cold fingers and always glad i had an extra. Plus you may take longer than you think on the bike, or more likely on the run. You definitely don't want to run out of nutrition on the run. That has happened to me before where I thought I would run a certain time but took a lot longer!
Food for thought. Pun intended.