Simple Sugars and Complex Carbohydrates - an Incompatible Combination

By Steve Born

Hammer Peak Performance Tip: Fuels that contain simple sugars or a combination of simple sugars and complex carbs can hinder athletic performance and cause digestive distress. For athletes, the ideal carbohydrate source is complex carbohydrates, such as the maltodextrin used in Hammer Gel, HEED, Perpetuem, and Sustained Energy.

If you've checked the labels of competing endurance fuels lately, you've probably noticed that many of them contain a combination of simple sugars - fructose, glucose, sucrose, and/or dextrose - plus a complex carbohydrate. The suppliers of these products claim that this combination provides a superior source of energy for endurance athletes. Unfortunately, athletes who fall for these claims are setting themselves up for disappointment or outright failure.

Hammer Nutrition fuels are intentionally formulated with complex carbohydrates, not a combination of simple sugars and complex carbohydrates. Why are we so adamant about not combining them? Simple: We want you to enjoy your workout or race; we want you to achieve your best possible results; and we want you to do that without having stomach issues such as bloating, cramping, diarrhea, and a host of others.

Simple sugars + complex carbs = trouble

Here's the deal: For efficient digestion, simple sugars need to be mixed in concentrations no higher than 6-8% to achieve an acceptable absorption osmolar value of body fluids (280-303 mOsm). That's it. The problem is that a 6-8% solution is a pretty weak mix. It will only yield about 80-100 calories an hour, which, for most athletes, is inadequate for maintaining optimal energy production.

Some athletes realize that, and they try to resolve the problem by making a double or triple strength batch of their simple sugar product. Unfortunately, that solution is now far too concentrated. It's much higher than 6-8% and, unless more water is consumed or added to the mix (potentially causing the athlete to over-hydrate), that concentrated simple sugar solution will not pass the gastric channels. Energy production is compromised and stomach distress is sure to follow.

The same problem occurs when an athlete fuels with a combination of simple sugar and complex carbohydrate. The beauty of complex carbs is that they match body fluid osmolality, not at a 6 -8% solution, but at a more concentrated 15-18% solution. Even at this seemingly high concentration, complex carbohydrates (such as the maltodextrin used in Hammer fuels) will empty the stomach at the same efficient rate as normal body fluids and provide substantially more calories (up to three times more) than simple sugar mixtures will. But when simple sugars and complex carbs are consumed together or in close proximity, the solution concentration will be greater than what either source can be efficiently digested at. As a result, you're likely to have less energy and some form of digestive trouble.

Bottom line

  • The higher a fuel's simple sugar content, the less can be absorbed immediately. That's because your body will only permit 6-8% of it in solution into circulating serum for fuel replacement.
  • Complex carbohydrate fuels are easily and more rapidly absorbed in a 15-18% solution. More calories are absorbed faster, and are available for energy production than from simple sugar fuels or a combination.
  • The ideal carbohydrate source for athletes is long-chain complex carbohydrates, such as the maltodextrin used in Hammer Nutrition fuels. Hammer fuels will meet all your energy needs without causing the stomach issues that can occur from simple sugars fuels.