Poke some holes in this study please

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Poke some holes in this study please

Postby Steelcyclist » Mon Sep 27, 2010 4:33 pm


Here's a link to a study that was released in Science Daily in August of 2006. The study basically says that Protein is not beneficial for endurance sport. ... 182003.htm

I use Sustained Energy, and many other Hammer products, and love them. Also, a friend and I have been discussing some problems with this studies conclusions amongst ourselves.

Everyone chime in on how you would dispute this article with friends who are "Sugar-ade" junkies?

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Re: Poke some holes in this study please

Postby steve-born » Tue Sep 28, 2010 1:13 pm

Hello Geoff -

Couple of thoughts come to mind:

1) Take a look at who is funding the study... a company that doesn't make a carbohydrate + protein drink.

2) Look at the duration of the test... it's 80 kilometers (or about 50 miles) in length, which would take about 2.5 - 3 hours to accomplish.

3) Look at the number of test subjects... only 10 (hardly a study with a large group of subjects).

Those three things definitely "raise a red flag" to me. Now, here is some information on the benefits of using a "carbohydrate + protein" product during prolonged exercise, this information coming from Dr. Bill Misner, the now-retired head of Hammer Nutrition's R & D. Some of these may have a few repetitive statements in them but I've included all of them, as I believe they thoroughly outline our position on this topic.

In one correspondence to a client, he wrote the following:

I agree with your colleague's assessment of protein donors during the energy cycle as contributing between 5-15% of the calories recruited complimenting glucose through gluconeogenesis. However, in an endurance event lasting as short as 2 hours to as long as 12 hours, 0.5% separates first place from last place in various age groups or even the top 10 overall event winners. So who can give away 5% energy substrates from amino acids recruited from lean muscle mass and expect to place as high as the athlete who puts the fuel into circulation in anticipation of deficiencies?

This is what specific amino acids (consumed during exercise) impact energy metabolism:

*** Alanine can be utilized in the production of energy (by converting to endogenous glucose when insufficient endogenous glucose is available for the production of energy such as during exercise or fasting or in the presence of hypoglycemia).

*** Arginine and Ornithine (when consumed simultaneously) is reported to enhance the release of human Growth Hormone (hGH) which enhances the body's production of energy.

*** Citrulline & Aspartic Acid are reported to advance the production of energy.

*** Mortimore & Poso insist that glucogenic acids body's production of energy (after they have been metabolized to glucose within the liver).

*** Glutamic Acid (manufactured within the body from Glutamine) is utilized as a source of Energy within the Brain.

*** The correct dosage of glycine increases energy production after conversion to glucose in the liver.

*** Isoleucine helps to regulate energy levels by stabilizing and regulating blood sugar levels.

*** Leucine can be utilized within the body in the production of energy.

*** Phenylalanine (1,500 mg per day) assists energy production where norepinephrine deficiency exists.

*** Tyrosine increases energy production where a norepinephrine deficiency exists and also increases energy by contributing to thyroid hormones that increase the body's basal metabolic rate.

In my opinion, protein-enhanced carbohydrates consumption during exercise puts amino acid depleting substrates back into the systems repletion cycles for a small energy moiety but an even larger recovery mechanism for muscle glycogen storage and muscle amino acid anabolic activities.

--- END ---

In another correspondence he wrote:

The fact that your body is recruiting lean muscle amino acids from muscles to the liver when liver glycogen cannot keep up with falling blood glucose demands, we estimate that most athletes at a 70% VO2 Max rate pace will euthanize 10-15% lean muscle amino acids for energy requirements. If approximately 1 part of 8 is protein in a high carbohydrate drink, hypothetically the lean muscle protein cannibalization will be inhibited resulting in prolonged carbohydrate fuel sparing, lean muscle cannibalization sparing, faster post-exercise recovery and less exercise-induced muscle soreness."

In yet another correspondence he wrote:

As you may know, not all are agreed upon taking protein with carbohydrate DURING endurance exercise. Ivy and his colleagues at the University of Texas are convinced that protein potentiates the restorage of carbohydrate to glycogen stores. Mero suggested (1999), "Consumption of BCAA (30-35% leucine) before or during endurance exercise may prevent or decrease the net rate of protein degradation, may improve both mental and physical performance and may have a sparing effect on muscle glycogen degradation and depletion of muscle glycogen stores." MacLean et al.(1996) concluded that: (1) the administration of BCAAs can greatly increase their concentration in plasma and subsequently their uptake by muscle during exercise, and (2) long-term exercise following BCAA administration results in significantly greater muscle NH3, alanine and glutamine production, as well as lower lactate production, than is observed during exercise without BCAA supplementation. In all fairness, there are several others who take opposition to Maclean and Mero's implication and in fact several have shown in their collected data the limits to adding protein to carbohydrates for consumption during endurance exercise. The small donor soy protein we formulated in Sustained Energy, Perpetuem, and the even small quantity of BCAA's in Hammer Gel do not interfere with osmolar pressure issues, serum ammonia concentrations, or the caloric absorption rate of the carbohydrate solutions. The exception to this rule are when athletes overdose toward hypertonic solution or underdose toward hypotonic solution mixtures, which neither support caloric depletion nor optimal absorption rate pathways.


(1) MacLean DA, Graham TE, Saltin B. Stimulation of muscle ammonia production during exercise following branched-chain amino acid supplementation in humans. J Physiol. 1996 Jun 15;493 ( Pt 3):909-22.

(2) Mero A. Leucine supplementation and intensive training. Sports Med. 1999 Jun;27(6):347-58. Review.

--- END ---

We discuss this even more in the article "Proper Caloric Intake During Endurance Exercise" ( ... .1275.html).

As you can see, our position is that a "carbohydrate + protein" combination is preferable to a "carbohydrate only" fuel when exercise extends beyond about two hours.

I hope this will provide the information you're looking for!

Sincerely -

Steve Born
Fueling Expert
Event Sponsorship Coordinator
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Re: Poke some holes in this study please

Postby ssrknordic » Wed Oct 13, 2010 9:31 am

OK- For Starters an N of 10 is a very small number of subjects,
What are the variables measured for performance?
What was the experimental design( i.e. was order of drinks randomized, relative to test sequence so training effects and other variables were mitigated)
Would love to see the data, but if one guy had an off day (and this happens always when you have a design like his with many external variables that can corrupt your data) then your study findings go from nothing to significant.
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Re: Poke some holes in this study please

Postby Steelcyclist » Tue Oct 26, 2010 10:16 am


We also know very little about the participants themselves. Age, training level, consecutive test days?

With such a small group, one guys off-day could swing the study results by 10%?!

It's frustrating though, as these are the studies that are groomed to fit mass marketed sugar drinks. So they can point to "lab tested" results.

It does make the debate fun though with friends. What's always tricky is breaking folks of the "it's always worked for me" mindset. Opportunity cost of poor nutrition has "always (underperformed) for me" should be what my buddies say.

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