Calorie Confusion

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Calorie Confusion

Postby wibergda » Sun Feb 13, 2011 4:29 pm

In your knowledge sections, Hammer recommends 150-280 calories per hour or 240-280 calories per hour depending upon where you are reading. In the Perpetuem product usage guide, Hammer recommends 101-270 calories per hour depending on your weight. To me this is confusing, having all these different calorie suggestions. As a reference, I am a competetive ultra endurance mountain biker who is 41 and weighs 151 pounds. I tend to race for 10 hours at an average heart rate of 149 bpm and my lactate treshold is 166 bpm. My max HR is 183 bpm. You can see that my LT is approximately 91% of my max HR. I also almost always get an upset stomach about 3 to 4 hours into a race. So my question is as follows.

If I were to fuel with perpetuem only, do I use the recommendations on the bottle for total hourly calorie intake of 135-169 calories or do I consume closer to 240 calories per hour?

I would appreciate any feedback. I used perpetuem a few years ago and went away from it and tried many many other products. I am now coming back to perpetuem in hopes of getting rid of my little stomach problems. I have used up to 300 calories an hour which I am sure was too many. I am really trying hard, reading a lot, and trying anything to get rid of my issues. Thanks again for the help.
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Re: Calorie Confusion

Postby steve-born » Mon Feb 14, 2011 11:21 am

Hello wiberdga (please post your first name on future posts so that we know who you are!) -

I can see where your confusion may come in and I'll try to clarify that for you.

In the article "The Hammer Nutrition Fuels - What They Are and How to Use Them" ( ... .1275.html), in the section entitled "Key things to remember regarding fueling" (near the end of the article), we discuss our rationale regarding proper fueling in stating:

A) The goal in fueling is not to try and replace all the calories your body is burning with equal to near–equal amounts from your fuel. As explained in various articles found in The Endurance Athlete’s Guide to Success, and in back issues of Endurance News, the human body is not equipped to replace “X” out with “X” or “near–X” in. Fortunately, the body has many built–in mechanisms that effectively bridge the gap between what it’s losing and what it can comfortably accept in return from your fuel donation. That’s why your focus should NOT be “How many calories can I consume before I get sick?” but rather, “What is the least amount of calories I need to consume to keep my body doing what I want it to do hour after hour?”

Fueling this way—the “less is best” approach—makes much more sense, if only because a “not enough calories” problem is significantly easier to fix (you simply consume more calories) than an “uh oh, I overdid it on the calories” problem.

B) During exercise, the average–size athlete’s liver can effectively return 4.0 to slightly over 4.6 calories per minute back to the energy cycle. That's 240 – 280 calories per hour MAXIMUM for the average–size athlete under normal conditions. However, we have consistently noted that most athletes do well on even fewer calories, so "average size" athletes (approximately 160–165 lbs/approx 72.5–75 kg) should look at that 240 – 280 gauge only as a reference point (you’ll notice that our recommendations are even less than those amounts). Of course, larger athletes on occasion may need slightly more calories and lighter athletes will most certainly need fewer calories.

Larger athletes on occasion may need slightly more calories, lighter athletes will most certainly need fewer calories, and "average size" athletes (approximately 160–165 lbs/approx 72.5–75 kg) should use the 240 – 280 gauge as a starting point, if not lower.

C) All athletes must be willing to alter their calorie intake in deference to the weather, the terrain, their pace, and any pre–race anxieties they're experiencing, as all of these things negatively affect optimal digestive system functioning.

With this in mind, here are our suggested dosages for the following Hammer Nutrition fuels. As just mentioned, over the years we have consistently noted that for optimal performance most athletes require far less than the theoretical maximum of 240–280 calories/hour. This is why we recommend starting with the lowest amount suggested, especially if your weight is at the lower end of the scale, and increase the amount of calories you consume if you find it necessary.

Remember, though, that these are just suggestions and that you need to determine, via thorough testing under a variety of conditions, what amounts work best for you.

-- END --

Specifically regarding Perpetuem, we provide the following dosage suggestions, along with some additional important info specific to this fuel...

Suggested Doses by Body Weight*:

* 0 – 120 lbs (approx 54.5 kg) – up to 3/4 scoop/hr. This provides approximately 101 calories.
* 120–155 lbs (approx 54.5–70 kg) – 1 scoop/hr. This provides 135 calories.
* 155–190 lbs (approx 70–86 kg) – 1.25 to 1.5 scoops/hr. This provides approx 169 to 202.5 calories.
* 190+ lbs (86+ kg) – up to 2 scoops/hr. This provides 270 calories.

*These are estimated doses. Each athlete should determine in training, under a variety of conditions, their personal optimum.

Special Note on Perpetuem: Due to this being a high concentration calorie source (via its complex carbohydrate, soy protein, and healthy fat components), we have noted that many athletes do well with a substantially lower calorie intake when using Perpetuem as their primary–to–sole fuel. Therefore, with this particular fuel we highly recommend starting with the lowest amount suggested—perhaps even a bit lower—and work your way up to a higher amount, if a higher amount has proved to be necessary via testing in training.

-- END --

At your weight I would suggest an hourly intake of Perpetuem of 1.0 - 1.5 scoops per hour. That will supply you 135 - 202.5 calories per hour. I can tell you that Brian Frank (company owner) @ 165-or-so lbs uses only 1.0 scoop an hour. Personally, I think that's a tad low for him but he swears it works for him. So you might want to try that amount to start, understanding that you can always increase your caloric intake if that amount (1.0 scoop/hour) is proving to be inadequate.

I hope this helps answers your questions and clarifies things for you. Please let me know if you need more information.

Sincerely -

Steve Born
Fueling Expert
Event Sponsorship Coordinator
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