Dr Mark Cucuzella, far left, running the Comrades marathon. Under his t-shirt is a belt that carries his flask and an electrolyte product. Picture: SUPPLIED
Dr Mark Cucuzella, far left, running the Comrades marathon. Under his t-shirt is a belt that carries his flask and an electrolyte product. Picture: SUPPLIED

The human body is made up of lots of water — somewhere between 55% to 78%. It makes intuitive sense, then, that water is the best drink during prolonged exercise.

The percentage of water in a body depends on age, gender and levels of fitness, say experts. That’s because fatty tissue has less water in it than lean tissue. Women naturally have more adipose (fatty) tissue than men.

Yet while most experts say water is the optimal drink, there are caveats. And as with all good things in life, too much can be bad.

“If you are a recreational athlete, you only need water,” says Cape Town sports scientist Prof Tim Noakes. “If you are an elite athlete, you may need more than water.”

Noakes is author of the best-selling book Waterlogged: The Serious Problem of Overhydration in Endurance Sports. In it, he dispatches the mantra that experts have repeated to athletes and coaches for decades: “Drink as much as you can, even before you feel thirsty.”

“The overhydrated athlete is at risk of exercise-associated hyponatremia [EAH] — a potentially fatal condition,” he writes.

Noakes documents how this mantra allowed bottled water and sports drinks to grow into billion-dollar industries over a short period, and the distortion the soft-drinks industry produced to market high-glucose drinks. “They never spoke about the downsides, which include dental caries,” he says.

Many athletes have “the worst teeth” from drinking high-sugar drinks all day, every day — and perhaps increased diabetes risk, he says.

But all athletes may sometimes need a high-sugar drink, Noakes adds. Some evidence shows that glucose acts as a brain stimulant (in other words, a drug) and helps with performance in that way. But athletes on a high-carbohydrate diet must ingest carbs at higher rates whenever they run more than two to three hours.

“Fat-adapted athletes don’t have that problem,” Noakes says. “They can do any exercise longer than that purely by burning their fat [instead of glucose] stores, which they filled up the days before by eating fat.”

US physician Dr Mark Cucuzella agrees. He practises family medicine in West Virginia and is a professor at West Virginia University School of Medicine. He is also a US Air Force reserve lieutenant-colonel who created its Efficient Running Programme. He has run competitively for almost 40 years and has more than 100 marathon and ultramarathon finishes under his belt — including his second Comrades this year.

Cucuzella is author of Run For Your Life, published this month. The book aims to help athletes run, walk and move without pain or injury — and to enjoy the sport. US Marine Corps coach Joe Puelo says Cucuzella has taken back the running paradigm that major shoe companies and the mass media have fostered. He has recalibrated it with “the runner’s best interests at heart”.

Cucuzella says water is the best drink, but for events lasting more than two hours some people, especially those who perspire heavily, benefit from sodium, magnesium and potassium as electrolytes mixed with the water.

He used to think that Gatorade, Pepsico’s flagship range of sports drinks, was a required nutrient for marathons. “But now, I know better,” he says. “Water and electrolytes are fine. If your brain senses you need a little sugar, diluted sports drinks usually do the trick. A little sea-salt in fruit-infused water also works.”

Cucuzella recommends water with a product that has no calories, is packaged with small straws and mixes easily with free water for athletes who sense they need some electrolytes. He uses the product for long runs on hot days. It “preloads” him with fluids and allows him to carry less while running.

For this year’s Comrades, Cucuzella drank mostly water, with the product carried in a belt. He mixed it at aid stations in a flask he also carried with him. And once he passed the 50km mark, he took an “occasional hit” of Coca-Cola.

“During ultramarathons, the body’s cells, and maybe even the brain, can utilise the glucose immediately. It acts like a little turbo boost,” he says.

His body was still burning fat primarily as the fuel source, Cucuzella says. The glucose “just gave it a spark, so to speak”.

But there is no one-size-fits-all recipe for optimum hydration during endurance events, he adds. “Everyone is unique in their needs so people should rehearse.”

And athletes should remember that “race day and adaptations during training are two different things”. For that reason, Cucuzella never drinks sugar drinks during training — to teach his body to “burn fat” on race day.

 •Sboros is founder and editor of Foodmed.net