Sports drinks are playing an increasingly important role in the modern age. Today’s athletes, as well as active people, are eager to learn more about the types of drinks that can help improve their overall performance. To supplement their tough training regimen, they are looking out for sports drinks that give them the energy to go even further in their sport.
For these sports people, it is essential to supplement their training with the right nutrition before, during and after their exercises to increase their wellbeing.
Carbohydrates are central to sports and exercise performance. According to modern dietary guidelines, an average person should obtain about 55 to 60 percent of daily energy from carbohydrates, equivalent to eight g per kg of body weight.
Athletes rely on carbohydrates because they are easily available to provide the essential source for physical performance—glucose. In cases of endurance exercise lasting more than one hour, sports drinks with six to eight percent carbohydrates should be consumed in amounts of 800 ml per hour.
Most popular sports drinks contain high glycaemic carbohydrates like maltodextrin, glucose syrup and sucrose. They release glucose into the bloodstream at a fast rate, which can result in large spikes and drops in blood glucose levels—not an ideal situation for athletes.
However, ‘slow release’ carbohydrates such as isomaltulose, also known by its trade name Palatinose, which deliver a balanced release of energy over a longer period of time, are an interesting alternative. Scientific research has shown that isomaltulose has a sustained effect on normal blood glucose levels compared to other fully digestible carbohydrates.
Carbohydrates are undoubtedly important in sports. To understand the science behind it, the relative importance of carbohydrate and fat oxidation to fuel active muscles during exercise and the influence of additional carbohydrate intake on this need to be considered.
A recent meta-analysis concluded that carbohydrate supplements with an appropriate composition and administration can potentially offer significantly improved endurance performance. Exercise involves powering muscles with energy from carbohydrates, mobilised from the body’s own sources, such as glycogen, or fat from fat reserves.
Particularly during intense exercise, the preferred substrate for energy conversion is carbohydrates because of their more efficient energy supply. However, glycogen stored in muscles and liver is limited to about 1,750 kcal.
During prolonged endurance exercise at high intensity levels, these stores get depleted and are then no longer sufficient to support endurance activity at high intensity. In contrast, body stores of fat are large (around 80,000 kcal), but the conversion of these into energy is much slower than that of carbohydrates.
Theoretically, based just on carbohydrate stores, the average athlete exercising at approximately 75 percent of his maximum oxygen uptake (75 percent VO2 max) could last only about 80 to 100 minutes before glycogen depletion occurs, followed by a drop in performance.
However, in practice, athletes are capable of much longer endurance events, such as marathons. The challenge is to use the body’s fat reserves to a greater extent in the fuelling of the muscles.
What role can the carbohydrate choice with sports drinks play in this?
Two aspects are important to understand the interplay in this. Firstly, carbohydrates consumed with foods or sports drinks are used first in the energy supply to the muscle, simply because this allows the body to save its carbohydrate and fat reserves for times when no ‘external’ sources are available.
Secondly, the rate of glucose supply from those drinks determines the extent to which mobilisation and utilisation of internal sources are suppressed. This means that carbohydrates providing fast glucose to the body lead to a more extensive suppression of fat utilisation.
This is where the advantages of isomaltulose become evident. The ‘slow release’ carbohydrate, which provides its carbohydrate energy more steadily over a longer time, allows the body to maintain a higher level of fat utilisation in the fuel mix to the muscles.
In endurance exercise, a higher contribution of fat oxidation is said to have a glycogen sparing effect and thus a beneficial effect to enhance endurance performance.
Breaking Down CarbohydratesA study at Freiburg University investigated the impact of different carbohydrates on exercise performance. Researchers looked at how the differences in fat oxidation during exercise could influence endurance performance as result of delayed glycogen depletion in trained athletes.
Athletes started by consuming a carbohydrate drink before an endurance exercise. This exercise period was followed by a time trial test to assess endurance performance. On one day, the athletes consumed a drink with maltodextrin; on another day, the same athletes consumed a drink with isomaltulose (cross-over study design).
The results showed that the participants demonstrated a sustained blood glucose response and lower insulin levels, leading to higher fat oxidation rates during the endurance exercise, after having consumed the drink with isomaltulose. Moreover, the athletes were able to perform at least equally well, if not better, with the isomaltulose drink compared to the maltodextrin drink.
Taro Taylor, Sydney, Australia
Boosting fat oxidation may also be important for those wishing to maintain a healthy body weight and body composition. According to the World Health Organization (WHO), obesity is a major issue in Southeast Asian countries with obesity rates running at approximately 30 percent for Malaysia, 26 percent for Singapore and 19 percent for Thailand.
Various studies have established that isomaltulose increases the proportion of energy derived from fat in overall energy consumption. This applies both to athletes and to those leading less physically active lives.
While the energy balance (the ratio of calorie intake to calorie expenditure) is important, isomaltulose does not increase the basal metabolic rate, ie: the amount of energy expended when a body is at rest.
Isomaltulose acts by increasing the fat burning rate, or the proportion of overall energy production that comes from fat oxidation. An increased fat burning rate means that active consumers can draw on their carbohydrate reserves for longer, and at the same time, burn fat more effectively.
The results indicate that isomaltulose can play a decisive role in weight management. While playing sport or taking part in exercise, athletes can derive a dual benefit from the functional carbohydrate—energy in the form of glucose is available for a longer period during endurance sports, while a greater proportion of energy can be released from body fat. This prevents total depletion of carbohydrate reserves, enhances endurance and contributes to an athletes’ performance when active.
Natural OptionIsomaltulose is derived from pure beet sugar and is also found in honey and sugar cane as a natural component. With a mild sweetness, its sensory profile is very similar to sugar, without any aftertaste.
At the same time, sports drinks produced with isomaltulose maintain a constant osmolality even in acidic and pasteurised beverages, regardless whether they are isotonic, hypotonic or hypertonic. This means the amount of solute particles of salt, minerals or protein remains stable during the complete shelf life. With isomaltulose, new and modern concepts of a sports drink are possible, providing prolonged energy with a mild and natural sweetness.
In addition to the intense training, maintaining their diets and also preparing their minds for the next competition, endurance athletes can look to sports drinks which are more specifically targeted to their needs and thus have the potential to further boost their performance levels.
However, their importance and key benefits lies beyond what’s in the bottle. Learning more about the ingredients that go into the drink can help them make informed decisions and choose the sports drink that will truly help them go the distance.