Training & Nutrition - Can this be right?

Not sure whether to post this in here, Clydes, or Triathlon but this seemed the most logical.

I read an article in "Triathlete" that says during long races (i.e. Half Ironman) a male should consume 1.1 grams of carbs each hour per Kg of his weight. So given that I weigh just about 100 Kg, that's 110 grams or 440 calories of carbs per hour. Wow! That seems like a lot!!!

Let's assume that I do the race in 6:30...that's 2,860 calories of carbs only...so I'll probably end up consuming 3,500 or more. That seems like it will be tough to do while biking and running.

All that said, I will admit that I seriously bonked at mile 6 of the run in my last Half IM and it took drinking a lot of coke to get back in the groove...so I guess this could be right.

Anyone have any experience with this?

Cheers.
-CJ

True, assuming two things:

1) You're of average triathlete weight

(yeah right, only top triathletes are average, if we were all average triathlete weight we'd be in the top 10%) ;)

2) That you're racing above your general aerobic pace, that is burning less fat and more glycogen.

So given that I weigh just about 100 Kg, that's 110 grams or 440 calories of carbs per hour. Actually, it seems about right on. The only question is whether or not you actually have the proportion of lean body mass as well as aerobic conditioning to need 440 cals per hour.

If you are a slower athlete, and metabolize a greater proportion of fat during competition then it's likely you get by with significantly less refueling during events. If you mobilize even an extra 4oz of fat, you would require 700-900 calories less during the race.

I saw on a triathlon website a video explaining proper nutrition during an event like an Ironman or Half-Ironman. The guy said something like you need to roughly know how many calories you going to burn per hour. He said a lot is based on bodyweight, speed, ect... Then you don't try to replace calorie for calorie lost, but you try to replace about 25-30% of the calories lost per hour. So if you burn 500 calories per hour you should take in about 125-150 calories per hour. If you burn 1000 calories you would need about 250 calories per hour. I think the guys name is Dave Scott.

Thanks. I appreciate all of the answers.

I'm not sure anyone who is 220 lbs is of average triathlete weight :) I'd say that I'm a good 30+ lbs overweight...working on it but I'm not all that good with diet...it is what is. I can be the fat guy that inspires spectators to do long distance tri's (as in, "if that guy can do it...").

Given my mass, I'm sure I work a bit harder than most in the events so I wouldn't be surprised if I was burning more glycogen than fat.

Thanks again...I have just over four weeks to get my nutrition plan in place. This helped.
-CJ

It's more about how many calories/hour you can move across the stomach wall. Larger people can usually move more than smaller people, I suppose having more square inches of stomach lining. You obviously can't replace as much as you burn, but you should try to replace as much as you can. The harder you go, the fewer calories you can process, a pity, but true. You just have to experiment with what you can tolerate at different levels of effort. You can also train yourself to process more, by slightly stressing your system. 250 calories/hour is a good starting point. If you can manage that, you should be fine. IME, 440 calories/hour continuously is impossible for the average athlete.

I always figure 250 cal/hr for long cycling events, and if I do that right from the start, I don't have problems. Since you start with the swim, you're going to be running behind right from the start, so you'll have to start fueling ASAP on the bike.

Looking back at my records, on 7-10 hour events I burn about 750 cal/hr. Of course that's just me, and I'm a lot lighter than you, 156 lbs. presently.

Not sure whether to post this in here, Clydes, or Triathlon but this seemed the most logical.

I read an article in "Triathlete" that says during long races (i.e. Half Ironman) a male should consume 1.1 grams of carbs each hour per Kg of his weight. So given that I weigh just about 100 Kg, that's 110 grams or 440 calories of carbs per hour. Wow! That seems like a lot!!!

Let's assume that I do the race in 6:30...that's 2,860 calories of carbs only...so I'll probably end up consuming 3,500 or more. That seems like it will be tough to do while biking and running.

All that said, I will admit that I seriously bonked at mile 6 of the run in my last Half IM and it took drinking a lot of coke to get back in the groove...so I guess this could be right.

Anyone have any experience with this?

Cheers.
-CJTypically 200-250cal/hr is the maximum that you can digest and absorb through your intestines per hour. Extra amounts above this will cause slower gastric emptying and possible dehydration.

If you're doing the race in 6:30 and burn off 3500 calories, that's a 540cal/hr pace and depending upon your fitness and conditioning, a portion of those calories can come from fat. Let's say you're going a little below LT and are burning energy at a 90/10% glycogen/fat ratio:

3500 TOTAL CALORIES
350 calories from fat

3150 calories from carbs
-2000 calories stored glycogen
------------
1150 calorie deficit
/ 6.3 hours = 175 cal/hr roughly

If you start taking in 200 cal/hr right from the start, that should be sufficient to ward off the bonk completely. If you slow down the pace, then you'll be able to burn a larger percentage of fat and won't need to eat as much.

Typically 200-250gm/hr is the maximum that you can digest and absorb through your intestines per hour. Extra amounts above this will cause slower gastric emptying and possible dehydration.


That's 800-1000 calories? That's while you're exercising?

You actually mean 200-250 calories per hour right?

You actually mean 200-250 calories per hour right?Yes that's right. I correct my post, thanks! :)