Supplement Savvy - 6/24/05.

Once again it's time to summarize some more studies from the ACSM Conference. The abstracts I will speak of today include Creatine Supplementation, Cortitrol Supplementation, and L-Aspartate.
Once again it's time to summarize some more studies from the American College of Sports Medicine Conference. There were over 2,500 abstracts presented this year, meaning there are surely a few dozen that relate to this audience.

The Effect Of 5 days Of Calorie Free Creatine Supplementation On Repeated Sprint Cycling

Abstract # 235

Creatine itself is calorie free. However, as you are probably aware, there are dozens of products that combine some type of carbohydrate with creatine to enhance the uptake. Well, recent research has suggested that it may not be the carbohydrate that's necessary for uptake, but it may actually be a sodium dependent process.

Therefore, in the first study of its kind that I'm aware of, these researchers measured the effects of 5 days of creatine (20g/day, like a loading phase) vs. a plain maltodextrin powder. The purpose of the study was to determine the effect of 5 days of creatine with sodium supplementation on repeated sprint cycling (3 * 30 second Wingate cycling).

Eight men and two women who were currently active volunteered for this trial. It was a randomized, placebo controlled crossover study.

Subjects were randomized to one of two protocols: placebo, which was 5 g maltodextrin powder plus 233 mg sodium bicarbonate, plus 175 mg potassium bicarbonate or 5.0 g creatine citrate plus 50 mg of sucralose plus 60 mg ascorbic acid (vitamin C) plus 6 mcg cyanocobalamin plus 233 mg sodium bicarbonate plus 175 mg potassium bicarbonate.

Both supplements were packaged identically to mask the product they were taking and both were taken in the same manner (5 grams* 4 times/day).

Subjects performed 3 Wingate protocols (essentially sprinting on a stationary bike); which included pre and post-peak and mean power in each of three tests that were analyzed.

    Results: Results demonstrated that there were no effects on mean or peak power from the creatine supplementation with sodium. Keep in mind this was the first study of its kind. In addition, this may not have been the right exercise to test; however, other studies have shown increases from "normal" creatine with the Wingate test. More results are clearly warranted.

Cortitrol Supplementation Reduces Serum Cortisol Responses To Physical Stress

Abstract #143

You've all surely heard of Cortislim, the famous infomercial product that claims to "control cortisol levels and decrease body weight."

Well, when one product is as successful in the sales department as Cortislim, there are surely going to be others attempting to mimic its ingredients and hopefully sell just as well.

The purpose of this study was to assess the effects of Cortitrol on serum cortisol concentrations prior to, during, and after a high-intensity resistance exercise protocol and on a resting day. This was a double blind, matched, balanced, placebo controlled, cross-over designed study (lots of big scientific words to discuss the control of the study and how supplements were distributed to participants).

Although the authors did not discuss what the exercise protocols were, they did have one group of participants exercise and another rest.

    Results:The Cortitrol supplement significantly reduced cortisol concentrations during exercise and rest and significantly reduced free radical production. None of the hormones measured (free and total testosterone, DHEA, and GH) were changed from the treatment.

    These data show that Cortitrol was effective at changing the normal physiological changes associated with exercise and cortisol and free radical production. Since this is the only study using this particular product, I'd hold off on running to the nearest store and buying it. I'd instead opt for natural ways to control cortisol levels; don't over train, get plenty of rest, eat optimally and provide the body the nutrients it needs.

Effect Of L-Aspartate On Power In Intercollegiate Athletes

Abstract #238

Previous studies have demonstrated that L-Aspartate may lower blood ammonia and subsequently improve performance (elevated ammonia can occur during high power demands). Therefore, the purpose of this study was to determine if L-Aspartate did in fact have any effect on peak performance power.

The subjects in this study were ten intercollegiate water polo players and nine competitive intercollegiate athletes in other sports primarily using upper body for power (tennis, surfing, etc). The athletes exercised to exhaustion using an arm ergometer.

(side note: if you have never used one of these or seen one of these, it essentially looks like bike peddles for your arms, so your shoulders fatigue very rapidly)

Subjects were randomly assigned to either 25 g L-Aspartate (divided into 2, 12.5 g doses) or placebo. Results demonstrated that the L-Aspartate group had a significantly higher power output than the placebo group. The water polo players showed a significantly greater power output between supplement and placebo; however, the "upper body" group did not show any significant improvements.

    Results: The results from this study can be extrapolated to suggest that L-Aspartate may be an effective ergogenic aid for competitive athletes in prolonged high-intensity power sports. However, it appears that L-Aspartate is not effective for shorter duration, "upper body" power sports like tennis. More research needs to be conducted before taking too much of this product; the authors suggest that more work should be conducted with protocols with exhaustion occurring between 30 to 60 seconds.


Once again that wraps up some more research abstracts from this year's ACSM meeting. Future articles will discuss the recovery impact of antioxidants, protein supplements on power and strength, glutamine, supplementing with fruit and vegetable juice concentrates, and more.

I'd like to reiterate that while some of the studies I have discussed presented significant changes and others have not, these are merely abstracts. Abstracts are typically the first step to a larger study and ultimately, publication of a full length manuscript. Until that time, all studies need to be considered among many other factors. Nothing is written in stone until multiple studies have been conducted on both safety and efficacy of a product.

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