Sucrose

Sucrose is a disaccharide composed of one glucose unit and one fructose unit linked by a glycosidic bond. It occurs naturally in sugarcane and sugar beet and is the familiar table sugar used in many foods and beverages.

Energy and hydration balance

Sucrose is used in sports drinks because it provides energy and helps maintain blood glucose during exercise. Each molecule is split by sucrase in the small intestine into one glucose and one fructose, yielding four calories per gram. The moderate glycaemic index of sucrose means it raises blood sugar quickly but not as abruptly as pure glucose, giving a steady supply of fuel. When dissolved in water, sucrose contributes to the drink’s osmolality; high concentrations can slow stomach emptying and lead to gastrointestinal discomfort. Formulators therefore keep total carbohydrate concentration between about 4 % and 8 % to balance energy delivery with rapid hydration. Because sucrose yields two different monosaccharides, it effectively increases the number of absorbable units without greatly increasing osmolality. This property makes it useful in multiple transportable carbohydrate strategies when combined with maltodextrin or glucose polymers. It also adds sweetness, which encourages athletes to drink enough fluid during prolonged exercise. However, large amounts can cause gas or cramping because the fructose transporter can be saturated.

Practical examples and notes

Dissolving 30 g of sucrose in 500 mL of water makes a 6 % solution, a typical strength used in ready-to-drink sports beverages. Some formulations mix sucrose with maltodextrin at a 1:1 or 2:1 ratio to combine rapid and sustained energy. Natural sources include sugar derived from cane or beet, but powdered mixes often use refined sucrose. When reading labels, check that the combined carbohydrate content stays within the recommended range to avoid stomach upset during intense exercise.

Sucrose supplies both glucose and fructose and is widely used in sports hydration formulas. Its balanced energy release and pleasant taste make it a common ingredient, but athletes should monitor concentration and combine it with other carbohydrates to optimise absorption.

Related Terms: Glucose, Fructose, Maltodextrin, Carbohydrate concentration, Multiple transportable carbohydrates