Drinking during exercise
During exercise, the body secretes a large amount of sweat, depending on the duration and intensity. This helps regulate body temperature. A lack of fluid intake quickly leads to a drop in performance.
Drinking during exercise therefore primarily serves to balance fluids. The drink should also balance the electrolytes that are excreted through sweat. Electrolytes are charged particles that are crucial for fluid distribution and water balance in the body. Sodium plays a particularly important role. Other electrolytes, such as magnesium, potassium, and calcium, should also be included in a sports drink due to their function in regulating nerve and muscle function. This is even more important if you are exercising for longer than 45 minutes. The carbohydrates stored in the form of glycogen also only last for 45-90 minutes. Therefore, carbohydrates should also be consumed during exercise after this time at the latest.
- Short exercise: anything less than 45 minutes. No energy intake (carbohydrates) necessary.
- Continuous high-intensity exercise: from 45 – 75 minutes: Small amounts, possibly just mouthwashes (yes, that’s enough and has been recognized as a performance-enhancing effect)
- Endurance performance: from 1 – 2.5 hours: 30 to 60 g KH / h
- Endurance performance: > 2.5 to 3 hours: up to 90 g kH / h
In terms of composition, a carbohydrate content of 4% to 8% (equivalent to 40 to 80 g carbohydrate/l) has proven to be favorable, since this concentration allows for a short residence time in the stomach and rapid transfer to the small intestine.
What is an isotonic drink?
This refers to a drink that contains carbohydrates and electrolytes. Isotonic drinks are liquids with the same osmotic pressure as human blood plasma, meaning the nutrient-to-liquid ratio corresponds to the ratio of our blood. As a result, liquids containing fast-acting carbohydrates and minerals are absorbed and digested more quickly. Thanks to the fast-acting carbohydrates and minerals they contain, the isotonic drink passes through the stomach faster and is absorbed into the bloodstream more quickly.
What does hypotonic and hypertonic mean in sports drinks?
Next to In addition to isotonic drinks, there are also hypotonic and hypertonic Drinks. All three terms describe the concentration ratio of dissolved substances in liquids to those in our blood. Hypotonic drinks have a lower concentration and are absorbed more quickly by the blood. The difference between isotonic and hypotonic is rather small. Here, too, it is much more important which carbohydrates the drink contains. Why Cluster Dextrin scores as a carbohydrate source is described in the guide Cluster Dextrin in Comparison.
Hypertonic drinks, on the other hand, contain more dissolved particles than our blood and take longer to be absorbed. Examples of hypertonic drinks include undiluted fruit juices, colas, and energy drinks. Hypertonic drinks place greater strain on the body during exercise and should ideally be avoided.
When are isotonic drinks useful?
For shorter and less intense workouts, water is usually sufficient. The minerals lost through sweating can be replenished through a balanced, healthy diet.
During intense exercise, it's worth compensating for fluid and mineral loss with an isotonic drink. The Performance isotonic sports drink contains one of the highest-quality carbohydrate sources with fantastic properties for use during training.
Is apple spritzer good during exercise?
The big advantage is their naturalness, as spritzers are definitely among the most natural thirst quenchers. Apple spritzers can be consumed during exercise, but sodium should be added. The main carbohydrate source, fructose, which is found in apple juice, is questionable. 100ml of apple juice contains 5.3g of fructose and 1.9g of glucose. Depending on the intensity, it is questionable whether this amount of fast carbohydrates is sufficient. Furthermore, there are people whose stomachs are upset by fructose above a certain amount. Fructose is absorbed differently by the body than other carbohydrates. We recommend fructose during exercise only in combination with another high-quality carbohydrate.
Is non-alcoholic beer useful as an isotonic drink?
Beer contains carbohydrates and minerals. Depending on the non-alcoholic beer, it is actually isotonic. Fundamentally, the question here is how well it is tolerated. However, it is definitely not absorbed as quickly as other isotonic drinks, and we suspect that the beer taste can be annoying during an intense training session. As an athlete, you probably don't want to smell like beer.
Difference between hypotonic, isotonic and hypertonic drinks
Hypotonic drinks:
- They contain fewer dissolved particles than the blood in the body (approx. 15 – 20g carbohydrates per liter as well as small amounts of sodium, potassium, magnesium and possibly some vitamins).
- They have a rapid gastric emptying and absorption rate, but a low energy content.
- They keep the fluid balance constant and are therefore a short thirst quencher but not ideal for long-term exertion.
- Example: mineral water, unsweetened tea, highly diluted fruit juice or spritzer (ratio 1 : > 3)
Isotonic drinks
- They contain approximately the same amount of dissolved particles as blood (they consist of water with a carbohydrate content of about 50 – 80g per liter, and also contain minerals and possibly vitamins).
- The amount of carbohydrates contained provides enough energy for acute physical exertion.
- Example: isotonic sports drinks, diluted fruit juices or spritzers (ratio 1:1 or 1:2).
Hypertonic drinks
- They contain significantly more dissolved particles than blood (approx. 10 – 14% carbohydrates, plus electrolytes and possibly vitamins).
- Hypertonic solutions are absorbed more slowly by the intestines because they require dilution in the stomach. This causes additional water loss from the body. Hypertonic solutions containing exclusively monosaccharides and disaccharides can also lead to diarrhea and flatulence.
- Hypertonic drinks are highly concentrated and high in calories, making them unsuitable as sports drinks.
- E.g.: soft drinks, undiluted fruit juices, malt beer, energy drinks.
One advantage of oligosaccharides is that they have lower osmotic activity than monosaccharides at the same energy density. Thus, they can be administered in higher concentrations without impairing fluid absorption in the small intestine.
