Sports Drinks

A sports drink or energy drink for endurance athletes is a powder or tablet that you dissolve in water into a drink that combines carbohydrates and electrolytes in the right concentration for rapid absorption during exertion. Unlike plain water, a sports drink replenishes energy and the minerals lost through sweat at the same time, which keeps both your fluid balance and your energy level on track during longer efforts. The core is the isotonic property: an isotonic sports drink has roughly the same osmotic pressure as blood, which allows the gut to absorb it quickly without a high sugar concentration slowing down gastric emptying or causing stomach complaints. That makes it the most direct way to replenish energy and hydration at the same time during active exertion.

The range covers four types: standard isotonic sports drinks in powder form with a carbohydrate and electrolyte mix for general use during endurance training, concentrated high-carb drink mixes for high carbohydrate intake at race intensity, electrolyte tabs that add electrolytes to water without extra carbohydrates, and caffeine variants for a mental boost in the final phase. All products come in powder or tablet form and are mixed into water in your own ratio. The choice depends on the duration and intensity of your training, the number of grams of carbohydrate you want to take in per hour, and whether you combine the drink with energy gels or energy bars as an additional fuel source.

Which sports drink is there?

The range is built up from four clearly distinct types, each intended for a different need and intensity level.

Isotonic sports drinks in powder

The most widely used category: sports drinks that you make yourself by mixing a measured amount of powder into a bottle of water. They contain carbohydrates and electrolytes in an isotonic concentration and are broadly usable in training sessions and races of varying duration and intensity. You can adjust the concentration by using more or less powder: less powder for short intensive training sessions or warm weather for faster hydration, more powder for longer endurance rides for extra carbohydrates. Available in larger cans or tubs for regular use and in smaller sizes for occasional purchases.

High-carb and multi-carb drink mixes

Concentrated drink mixes that deliver considerably more carbohydrates per serving than standard isotonic sports drinks. They were developed for race intensity where the body needs more than 60 grams of carbohydrate per hour and where a standard isotonic drink does not offer enough energy without causing stomach complaints. Many of these products use a combination of multiple carbohydrates with a high solubility, which means you need relatively little fluid per gram of carbohydrate. They are available as single-serving packs for on the go or in larger packs for regular use during intensive training blocks and race preparation.

Electrolyte tabs

Effervescent tablets that you dissolve in a bottle of water and that mainly deliver electrolytes: sodium, potassium, magnesium and calcium. They contain little or no carbohydrate and are intended for athletes who take in enough carbohydrates from other sources but want to compensate for extra mineral loss through sweat. They are also useful in warm weather, during long efforts with high perspiration, or when you mainly want to drink water but want to support the electrolyte balance. Their compact format makes them easy to take along to races and training camps.

Caffeine sports drinks

Sports drinks that, in addition to carbohydrates and electrolytes, also contain caffeine for a mental boost and extra endurance in the final phase of an effort. Caffeine lowers perceived exertion, increases alertness and, when used strategically in the last 30 to 45 minutes of a race, can give a noticeable performance difference. Do not use them in every training session but deploy them as a tool on race day or during the intensive final phases of long training sessions.

Which sports drink suits you?

The choice depends on the duration and intensity of your training, your carbohydrate needs per hour and whether you combine the drink with other nutrition sources.

You train 60 to 120 minutes at a moderate pace: choose a standard isotonic sports drink in powder and mix one bottle at standard concentration. At this training duration and intensity, an isotonic drink keeps your energy level and hydration on track without you needing extra carbohydrates from other sources. Use the remaining contents of the pack for multiple training sessions: bulk cans are more cost-efficient than single-serving packs with regular use.

You ride a cycling race, triathlon or an effort of more than 2.5 hours at high intensity: consider a high-carb drink mix alongside or instead of a standard isotonic drink. At race intensity you burn more than 60 grams of carbohydrate per hour and a standard drink quickly falls behind. A concentrated drink mix delivers up to 80 grams of carbohydrate per serving with minimal stomach load, which means you reach the required fuel intake without continuous topping up via gels or bars.

You exercise in warm weather or sweat heavily and want primarily to replenish fluid and minerals: choose electrolyte tabs in a large bottle of water. With high perspiration you lose more electrolytes than carbohydrates, and a strongly concentrated sports drink can put a heavier load on the stomach in the heat. Electrolyte tabs give you the freedom to vary the amount of fluid while keeping the electrolyte balance intact.

You are doing a triathlon and want to simplify your nutrition strategy: use a high-carb drink mix on the bike and switch to a lighter isotonic drink or electrolyte tabs for the run. On the bike you can drink easily and take in the largest part of your carbohydrates before the run phase begins. Switch from a sports drink to a lighter product for the run to relieve your stomach during the higher body movement of running.

You want to deploy caffeine strategically on race day: choose a caffeine sports drink for the last 30 to 45 minutes of your effort. Test this system in advance during a training moment at comparable intensity: not every athlete responds the same way to caffeine during exertion and the timing matters for the effect. Do not combine a caffeine sports drink with other caffeine sources such as caffeine gels to avoid overdosing.

Isotonic, hypotonic or hypertonic sports drink?

The three terms describe the ratio between the concentration of dissolved substances in the drink and in your blood. That concentration determines how quickly your body absorbs the drink and what it primarily offers: energy or hydration.

An isotonic sports drink has the same concentration as blood and is absorbed quickly by the intestines. It delivers carbohydrates and fluid at the same time and is the most versatile choice for most endurance sports. A hypotonic sports drink has a lower concentration than blood and is absorbed even faster, ideal when maximum hydration is the primary goal and energy is replenished from other sources. A hypertonic sports drink has a higher concentration than blood, delivers more carbohydrates per decilitre but is absorbed more slowly. It is intended as a fuel source when fluid needs are lower, not as a primary hydration drink during intensive exertion.

For general use in training and races, isotonic is the safest choice: rapid absorption, combined function and suitable for varying intensities. Use hypertonic variants only if you deliberately want to take in extra carbohydrates and know that you drink enough separate water alongside.

What do you look out for with sports drinks?

Carbohydrate content and carbohydrate type

Standard isotonic sports drinks contain between 20 and 40 grams of carbohydrate per 500 ml. High-carb drink mixes deliver 60 to 80 grams per serving. Choose the content based on your carbohydrate needs per hour, the duration of your effort and what you take along additionally in gels or bars. Also pay attention to the type of carbohydrate: products with a combination of glucose and fructose in a 2:1 ratio have a higher maximum absorption than products based only on glucose or maltodextrin, which makes the difference in stomach comfort when intake is above 60 grams per hour.

Sodium content and electrolyte profile

Sodium is the most heavily lost electrolyte through perspiration and is directly important for fluid balance. A good sports drink contains at least 400 to 700 mg of sodium per litre. Products with a low sodium content are less effective with high perspiration density or with efforts longer than 2 hours. Check the sodium content on the packaging and do not compare only on carbohydrate values. With heavy sweating or in summer, a higher sodium content is extra relevant for preventing hyponatraemia and muscle cramps.

Solubility and mix ratio

Not every sports drink powder dissolves equally quickly and completely in water. Powder that clumps or does not dissolve fully gives an uneven concentration in your bottle, which affects absorption and taste. Always mix the powder first with a small amount of water and only then top up to the desired volume. Check whether the product also dissolves well in cold water, because at races and training locations cold water is the norm. Tablets are predictable in this respect: they fizz up completely and give a consistent concentration.

Caffeine: deploy deliberately, not as standard

Caffeine in sports drinks has a measurable performance effect but works best if you are not used to it daily. Use caffeine sports drinks as a strategic instrument on race day or during intensive final phases, not as a standard training tool. Add up caffeine intake across all sources: if you already take along caffeine gels, do not add a caffeine drink or you risk taking in more than 400 mg of caffeine per day, which can cause restlessness, palpitations or stomach complaints.

Our advice: start with a standard isotonic sports drink as a base and test it in training at an intensity comparable to your races. Choose bulk packs if you train several times a week: the price per serving is considerably lower than with single-serving packs. Only invest in high-carb drink mixes if you structurally ride training sessions or races longer than 2 hours at high intensity and actually need more than 60 grams of carbohydrate per hour. For many recreational athletes that is not the case and a standard isotonic drink is sufficient.

Who is a sports drink suitable for?

• Triathletes who realise the largest carbohydrate intake on the bike and need a reliable drink mix for that which is well tolerated at race intensity, without being dependent on only solid gels or bars.
• Cyclists and road riders who regularly ride rides of 2 hours or longer and know that performance in the final phase of a ride is directly linked to how consistently they have replenished carbohydrates and electrolytes during the ride.
• Runners and triathletes on the run who are looking for a lighter alternative than a gel but still want to take in carbohydrates, and digest a thin isotonic drink more easily at the movement intensity of running.
• Athletes who sweat heavily or train in the heat and notice that drinking only water leads to muscle cramps, fatigue or headache in the second half of an effort, which points to an electrolyte deficiency.
• Beginning endurance athletes who train for longer than an hour for the first time and are looking for a simple, effective way to keep up their energy level and hydration without having to follow a complicated nutrition plan.

Need help with your choice?

Would you like to buy sports drinks but are you not yet entirely sure which formula best suits your training sessions and races? Then we are happy to help you further. You can reach our triathlon specialists by phone on +31 (0)413-256800, send an e-mail or drop by our triathlon shop in Volkel, the Netherlands.

Frequently asked questions about sports drinks

How many carbohydrates does an isotonic sports drink have per serving?

A standard isotonic sports drink contains between 20 and 40 grams of carbohydrate per 500 ml at a normal mixing ratio. The exact amount differs per product and depends on the mix ratio. Read the packaging for the recommended serving size and adjust the amount of powder to your carbohydrate needs per hour. For training sessions shorter than 90 minutes a standard concentration is sufficient; for longer or more intensive efforts you can consider slightly increasing the concentration or additionally using energy gels.

What is the difference between an isotonic sports drink and an electrolyte drink?

An isotonic sports drink delivers both carbohydrates and electrolytes and has as its primary function the simultaneous replenishment of energy and fluid during exertion. An electrolyte drink or electrolyte tab mainly delivers minerals such as sodium, potassium and magnesium, with little or no carbohydrate. Choose an electrolyte drink if you take in carbohydrates from other sources and primarily want to support the mineral balance, or if during shorter intensive training sessions you do not want to take in extra sugars but still want to keep an eye on the fluid balance.

Can I also drink a sports drink before training?

A small amount of isotonic sports drink before training can be useful if you ate a meal less than 2 hours before and still want a carbohydrate boost without solid food. It is not a requirement for training sessions shorter than 90 minutes if you have eaten normally. With pre-training intake, do not drink more than 200 to 300 ml to avoid a full feeling or stomach complaints at the start of the effort. The primary function of a sports drink remains replenishment during the effort, not as preparation.

How do I mix a sports drink at the right concentration?

Follow the mix ratio on the packaging as a starting point, but know that the recommended ratio gives an isotonic concentration at specific amounts of water. If you use more powder per litre than recommended, you make the drink hypertonic and slow down absorption. Always mix with the indicated amount of water or use less powder if you train in the heat and primarily want hydration. Test your fixed mixing ratio in training before you apply it in a race.

Can I combine a sports drink with energy gels?

Yes, but adjust the combination to your total carbohydrate intake per hour. If you use a gel with 20 to 25 grams of carbohydrate and drink an isotonic drink with 30 grams per 500 ml, you are already at 50 grams per hour at a modest drinking rhythm. Combine gels with water or an electrolyte drink without extra carbohydrates to avoid stomach overload, or use a high-carb drink mix if you deliberately want to head towards 90 grams per hour. Simplest rule: with gels always drink water or a light drink, not a concentrated sports drink.