Electrolyte is a scientific term for salts, specifically ions. These drinks are designed to simultaneously rehydrate and refuel during exercise. It is now generally accepted that a compositional range of 4-8 g/100 ml carbohydrate and 23-69 mg/100mL sodium is needed for replenishment of carbs en electrolytes.
A higher sodium (an electrolyte) concentration is needed to restore fluid balance and is useful for maintaining the thirst drive. Carbohydrates: Events lasting between 1 to 2.5 hours can take 30-60 g/h or ultra endurance events (>2.5 hours) 90g/h of carbs are recommended.
Electrolytes like magnesium, potassium and calcium may be included in sports drinks but current evidence indicates that no significant quantities of magnesium are lost so it is unlikely that additional magnesium will improve hydration goals or reduce cramping.
Protein or amino acids; Using proteins for recovery after exercise has good results and can be achieved by a range of sports products and everyday foods other than sports drinks. The benefits of consuming protein during exercise are contentious
Choose an electrolyte drink you like! Some are very high in sugar which can cause gastrointestinal discomfort. Electrolyte drinks are needed when you are exercising for more than 40-50 minutes.