Calorie/Carb Intake?

noonievut

I recently rode a 100km with an avg HR between my Aerobic & High Intesity level (I went harder than I usually would, as I was fighting a strong wind most of the way). When the ride was over, my HRM showed I had burnt 3,700 calories. I felt great throughout the whole ride but by the last 8-10km I had nothing left in the tank and struggled to make it home.

I think my fluid intake was fine as it was a cool day and I drank about 3 bottles of water and 1 amino, but I think I didn't have enough food. For this ride I started with 2 slices of toast w/peanut butter and espresso before the ride, then 1 clif bar, one granola bar and 1 gel during the ride. I spaced it out and thought all was good until the last part of the ride.

So, how does one calculate how many calories/carbs are required on a ride? Also, for 100-170km rides do you need more than bars & gels, or does it not make a difference?

Thanks.

noonievut

^bump^

If you have no information to provide, can someone at least point me to a web site that may...thanks.

sideshow_bob

4 grams of carbohydrate = 1 calorie. So to replace what your HR shows thats a load of food.

Different people have different requirements in terms of performance so it's hard to say for 100km you need X. It's also dependent on what you've eaten prior to the ride. For me personally if I have a couple of pieces of plain toast, 3 cups of cereal with a cup of skim milk and half cup of yoghurt and bowl of fruit 2-3 hours prior to a ride. I can ride (flat) 100km at race pace on a single powerbar that I cut into quarters and eat a quarter every 30 minutes with no problem. Some friends I ride with don't require any food during a ride like this ymmv.

I've ridden a number of 12 hour races and basically as long as I'm taking in around 600-800 calories (food+drink) every 2 hours I'm fine. So I'd say for your question of longer rides it becomes simply about continuing to fuel. I can't take that many calories by way of bars, mostly cause they taste so crap. for 100-170km, I'd say bars and other food, not bars alone.

--brett

discobean7

Other way around...
1 gram carbohydrate = 4 Cal
1 gram protein = 4 Cal
1 gram fat = 9 Cal
1 gram alcohol = 7 Cal

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noonievut

So the PowerBar Pria in front of me says:

170 calories
22g carbs (88)
11g protein (44)
6g fat (54)

I multiplied using your stats and if I add the 170 to the #'s in brackets I get 356 calories. Is this correct or do you not add the calories to the '=' calories? I want to know this so when I find out how many calories I need an hour for long rides I can calculate this. Thanks.

discobean7

Before and during a ride you need only be concerned with carbohydrates and hydration with hydration being the most important. For rides like you've described (100-170kms) or longer you should look to eat carbs in the amount of 4-5 grams/kg of body weight 4 hours prior to the ride. For shorter rides you could get away with 1-2 grams/kg of carbohydrate 1 hour prior to the ride. You might want to avoid the 1-hour strategy if you are prone to rebound hypoglycemia. With either the 4 or 1 hour strategy you can also take in 50-60 grams of a glucose polymer in a 50/50 solution with water (things like Gatorlode work). Take this solution about 10 minutes prior to or even during the first 15 minutes of a ride. For rides 60-90 minutes most can get away with just drinking water and not taking in any additional carbs. During rides our body is only able to use about 0.5-1 gram of ingested carbs per minute so your goal should be to replace this (i.e. take in 15-20 grams of carbs every 15-20 minutes). For example 8 ounces of Gatorade is 15 grams of carbs. Gels, bars etc. work too. You just have to calculate out the amounts. For hydration drink about 16 ounces 15 minutes prior to the ride. This can be the 50/50 solution described above. During a ride you should look to drink 6-8 ounces every 10-15 minutes (1 liter per hour). I think you said you drank 3 bottles during the ride, which if true, would not have been adequate. Dehydration may have played a role on your not feeling great by the end. This is more fluid than most of us tend to drink since it is tough to either carry or stop to get that many ounces, but again this is the ideal stategy for maintaining proper hydration. During extremes of heat the body can actually lose up to 3 liters of sweat per hour while only being able to absorb about a liter of water in the intestines. In this situation it's even more important to be properly hydrated before and to stay on top of your water intake early in the ride. I hope that helps.

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