It's no longer enough for regular Joes and Janes to work out for the good old 20 minutes of elevated heart rate. Hour-long—and far longer—stints in the gym, on the road or trail or in the pool are becoming normal. Marathons are gaining in popularity. Triathlons are seeing increased registration. Even ultra-, 50- and 100-mile marathons are not merely mocked as events for the insane. Once the turf of uber-athletes, endurance sports have become a way for everyone to get in shape, set goals and accomplish what they once thought impossible.
Along with the explosion of energy bars, electrolyte products are flooding the shelves to keep those fitness buffs working smart. From energy gels to electrolyte-rich drinks, powders and even blocks, keeping in top form no longer means grabbing a bottle of electric blue (or orange, red or green) hydration drink from Florida. Naturals companies are joining the race. But what should you recommend to your customers who are looking to enhance performance for their newfound uber-athlete selves?
What's so electric?
"Basically, electrolytes are mineral salts in your body. They're necessary not only for proper function, but for life—you can't live without them. Your body is an electrical organism, so it's sending signals back and forth throughout the cells, and the salts help those electrical impulses travel properly," says Chris Randall, brand manager for the Clif Shot line at Berkeley, Calif.-based Clif Bar. "There are five electrolytes: sodium and chloride, which make up generic salt, potassium, magnesium and calcium."
Consumers' knowledge of electrolytes can, in large part, be traced back to one brand. "One reason we think of [electrolytes] is great marketing from Gatorade," says Marie Spano, R.D., vice president of the International Society of Sports Nutrition.
Spano says a low level of blood sodium is known as hyponatremia. "My cousin had that about a year or two ago and he ended up in the hospital with seizures," she says. "Every year there's somebody that still dies from hyponatremia."
The kidneys are primarily responsible for retaining and removing electrolytes. "They control the balance of electrolytes in the blood, ensuring the body has all it needs to perform at its best," says Carol Dollard, chief operations officer at Whitestone, N.Y.-based Glacéau, maker of vitaminwater.
The minimum physiological requirement for sodium is 500 milligrams per day. The recommended daily allowance of potassium is roughly 3.5 grams per day.
According to a 2005 report on hyd?ration and electrolytes by the Dietary Guidelines Advisory Committee to the U.S. Departments of Health and Human Services and Agriculture, research on sodium and potassium levels is robust, but for the other electrolytes, recommendations are not as sure. The committee did conclude that in the United States less than 10 percent of adult men and 1 percent of women consume its recommendation of 4.7 grams per day of potassium, and less than 25 percent of adult men and less than 5 percent of adult women meet their daily calcium intake from foods of 1,240 milligrams per day.
Creating the power
The science of electrolytes is not nearly as easy to get right as one might hope. "It's challenging for somebody who doesn't have access or the desire to go into a sports lab and have that stuff tested. It's difficult to know how much you excrete," Randall says. "The gold standard would be to put you in a lab and run a test on you and see the volume that you sweat. Then a lab scientist would look at your sweat and what's in it." You could then base your supplementation around those numbers.
Spano says depletion is directly related to how much you are sweating. "A lot of it is how long you exercise, if it's hot out and, obviously, how hard you exercise," she says. "You lose about 1 gram of sodium for every liter you sweat."
A simple self-test for sweat rate is to weigh yourself in the morning, then go and do a prescribed amount of activity—usually about an hour—on a treadmill or an indoor Spinning bike, Randall says. "Then you measure how much intake of fluids you have, subtract your final weight from the start weight, add back the fluid that you took in, and that becomes your sweat rate. But what it doesn't tell you is what's in your sweat," he says.
Still, according to a January 2004 article in the Journal of Sports Sciences, "For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential."
A good starting baseline is to recommend that customers are at least meeting the RDA for all electrolytes, and then replacing the sodium and potassium that is more readily lost through sweat.
Jensen says it's important that people get to know their own bodies so they can make smart electrolyte choices.
Randall says many companies base their electrolyte profile on what's a reasonable amount to replace given that you don't need to do an exact one-to-one replacement.
Neurons also require electrolytes to carry impulses, so an imbalance can directly affect brain function. (In fact, bulimics experience brain-related difficulties, and doctors speculated that the Terri Schiavo saga may have been precipitated by an eating disorder-caused imbalance in potassium levels.)
Jensen says consuming an electrolyte beverage during the day may be helpful for daily brain function, especially if you skip meals. "If your blood glucose levels dip or your sodium or potassium electrolyte levels dip, you experience the same kind of things" as when you're participating in sports, Jensen says.
However, Randall is skeptical. "I'd have to say no, even if you skip a meal, you're not going to become electrolyte-depleted—unless your profession is teaching Bikram yoga or something and you do a few sessions without eating, but at your desk you're not going to deplete yourself. And again, real food has everything you need—assuming a relatively balanced diet."
But, as Dollard says, "Electrolytes help keep the body in balance, allowing you to feel and perform at your best."
Natural Foods Merchandiser volume XXVIII/number 4/p. 32, 34