Email Bag: Sports Drink Post Ignites Virtual Maelstrom

A few days ago FOA Anonymous Economist raised some questions about the benefits of sports drinks. Her comments ignited a virtual maelstrom (Or would it be a firestorm? And what's the difference between a hockey fracas and a melee?) of two excellent email responses to Activeness. Here they are.

By George!

George, a local endurance athlete who just clocked an impressive 11:21:14 at Ironman Lake Placid in August (congrats!) is a graduate student at SIU-Edwardsville in the Exercise Physiology program. He studies carbohydrate metabolism during exercise and therefore says he keeps up-to-date on much of the primary scientific literature. He responds to the Anonymous Economist's comments on sports drinks:

I think much of what Economist stated served more to jar a reaction rather than provide useful information. But regardless of the intention, I'd like to explain one of the misleading examples provided...the pH of drinks. When you compare pH of solutions (1 vs. 2), it is a logarithmic scale. This means that there is a 10-fold difference from one number to the next. pH of 6 is ten times more acidic than a pH of 7. ph of 1 is 100 times more acidic than 3. So comparing Gatorade to battery acid is just plain silly given the enormous difference that actually exists. Here is the web site she pulled her numbers from. As you can see most of what we drink (in terms of soft drink/sports drink) is in the low 3, upper 2 range. This is very tight on the absolute scale. The only oddball in the group is battery acid. I don't like these scare tactics.

As for recovery... Everything she stated is hardly supported by any scientific literature from the best minds in the field. I only need to direct everyone to the book Nutrient Timing by John Ivy, Ph.D. and Robert Portman, Ph.D. These two gentlemen are among the best in the world in on the subject of nutrition and exercise performance. In their easy-to-read book they cite all the scientific publications validating their statements. So picking at the Economist's statements point-by-point.

* Growth hormone rises only minimally with endurance exercise, and what this does to the body is largely unknown. When exercise stops, there is a transient drop of growth hormone — it doesn't persist after exercise. Growth hormone has not been connected to insulin regulation as supported by the scientific literature.

What is known is that both hormones rise following exercise...growth hormone is involved in bone growth and protein synthesis and insulin helps in glycogen replenishment (carbohydrate storage in the body). This means your body is craving carbohydrates to rebuild the depleted muscles and you are VERY insulin sensitive. Sports drinks are perhaps one of the greatest tools to faciliate this since they both rehydrate and replenish lost glycogen. In fact, many studies have shown that during exercise and following a workout, high GI foods (typically foods/drinks high in sugar) are the best things to have. During exercise blood glucose levels are maintained at a steady level and liver glycogen is spared from usage since outside sources of glucose are available. This prevents the "bonk" effect. During recovery, these foods increase the time to recovery since your body can quickly absorb this and replete lost muscle/liver glycogen.

* Calories do not "go anywhere" as they are units of energy, not tangible molecules. I believe she's saying fat is being deposited at the abdomen. But fat does not localize to one place, it goes everywhere in the body. The reason it appears to build up at the abdomen is that is where the most fast cells reside in humans. Fat cells (except in rare, extreme obese cases) do not multiply, they just get larger.

* "Insulin resistance stimulates aging." So does not dying at the end of the day.

* Triglycerides (TGs): I can't tell if she's claiming that sports drinks have TGs or not, but they don't. I assume she's stating that by drinking sports drink we will have too many carbs around for our body to deal with the extra fat that is around. Metabolism of fats and carbs occur together — there is no pecking order. Sure fat metabolism occurs at a greater rate if no carbs are present, but this is basically the Atkins diet...and we see how well that worked. Your body needs carbs in order to metabolize fat without creating a harmful ketotic-filled environment, which is not healthy. A healthy balanced diet should solve that along with exercise (which sports drinks help facilitate).

* She's right, she hasn't read the right literature.

Finally, I do agree with you in that sports drinks really function to serve the athlete. And for the non-athlete, just like all dietary advice, moderation is key.

Thanks, George!

The Marshall Plan: Low Sugar

FOA Marshall raises a question about the safety of artificial sweeteners:

We know most sports drinks are sugary running parallel to sodas. Has anyone researched the safety of heavy consumption of artificially sweetened/no-sugar drinks. Of course the FDA would never let a product go to market unsafe right? (Splenda, Nutrasweet, Sweet 'n Low, et al.) I live off sugar free Kool-Aid, log it on ice on my rides...but can anyone say how much is too much? Not sure what I would drink instead of that good old Tropical Punch or Grape? It's in almost everything low-carb these days, even "lite" lemonades, ice creams, and yogurts....and JPD's Propel.

Good question, Marshall. I've had relatives who were obsessed about eliminating artificial sweeteners from their diets but who never exercised and ate lots of fast food. Guess it's easier to cut out Diet Coke than to make real lifestyle changes.

I defer to new Activeness nutritional consultant George's expertise here, but I do know that the National Cancer Institute says there is no clear evidence that artificial sweeteners are related to cancer risk in humans. Artificial sweeteners are regulated by the U.S. FDA, which also rubber-stamped Vioxx and recently stated that marijuana has no medical value, so their approval doesn't mean a helluva lot to me. But for what it's worth: the FDA has approved aspartame, saccharin, acesulfame-K, neotame, and sucralose as food additives. Seems like I remember reading that if a mouse were to drink 100 Diet Cokes in a day, he would at least get a tummy ache. But don't quote me.