Nuun Active Hydration
As mentioned there is no carbohydrate at all in the tabs and the benefits of having a carb free sports drink are numerous. For starters less sugar is so much better for your teeth – worryingly dentists reckon racing cyclists are identifiable by sugar damage to the same two or three teeth always used to clamp down on their drinks bottle; Nuun’s drink provides fewer calories which is great for training when you are trying to improve that power to weight ratio; no carbs helps you avoid those sugar highs and lows; and it doesn’t create a mouldy, bio-mess in your bottles.
Most importantly though, carbohydrates can slow the rate at which your stomach empties, delaying the absorption of your drink and therefore its ability to hydrate you. This is particularly important in hot weather but is still relevant to cold weather training when you may be sheltering beneath multiple layers. There is a mass of scientific research suggesting we should worry as much about dehydration in performance cycling as glycogen replacement.
The concentration of dissolved salts and sugars in a drink, known as its osmotic concentration or osmolarity, determines how fast fluid can cross from your digestive tract into your bloodstream, where it will re-hydrate and replenish you. Carbohydrate can increase the osmolality delaying a drink’s absorption beyond the stomach. As a dissolved Nuun tablet in 500mls of water makes a hypotonic solution, the body absorbs it faster than a carb based sports drinks (an isotonic or hypertonic drink) and even water alone, so fluid and electrolyte balance is fully restored.
Nuun also provide all of the electrolytes you might need. They reckon that depending upon the temperature, cyclists need about 500–1000mg of sodium for every litre of water they consume which is up to three times the sodium amount that traditional carb sports drinks provide. Nuun hedge their bets giving you a useful 700mg per litre.