Demystifying sports drinks

ENERGY, endurance and recovery – these are some of the primary characteristics that attract athletes to seek out the best option for them in terms of fluid replenishment that is not just good old plain water. Sports drinks fall square into this category and have been a go-to for many athletes for post-workout rehydration for over 50 years, ever since the invention of the first ever sports drink, Gatorade, in the 1960s[i].

Sports drinks have taken quite a hard hit to the reputation in the past decade, however, especially in the United States after Texas Rangers baseball player Josh Hamilton was forced to sit out five games due to ‘blurred vision and balance issues’, officially claimed by the athlete to be due to ocular keratitis caused by ‘too much caffeine and energy drinks’[ii]. Notwithstanding the fact that this has been disputed by some[iii], the fact that energy drinks were mentioned gave all drinks connected to sports and physical activity a bad reputation almost overnight – with the greatest irony lying in the fact that that sports drinks and energy drinks are in fact two very different types of beverage.

Sports drinks are designed to help athletes and others engaged in intense physical exercise with rehydration.

Sports drinks vs. Energy drinks: A world of difference

A key difference between the two that needs to be highlighted is that of their respective ingredients and compositions. Energy drinks are products that aim to increase alertness and enhance mental and physical performance[iv], and as such the key ingredient in these are stimulants, most commonly caffeine and/or sugar. Red Bull is probably the most well-known energy drink brand in Asia, and according to their website, one 250ml can contains 80 mg of caffeine, which Red Bull states will help ‘improve concentration and increase alertness’[v]. Sports drinks, on the other hand, are formulations that target swifter and more effective rehydration in athletes or those who have undergone or are undergoing strenuous physical activity. The main ingredient in terms of the proper rehydration process is carbohydrates and electrolytes, which makes these the main component of sports drinks formulations[vi].

Apart from this, another important difference between the two is the recommended time of use. Though the temptation to consume just about any liquid during a physical workout when the body is dehydrated and/or warmed up and perspiring may be strong, experts do not recommend that this be done with energy drinks, mostly due to its caffeine content. Caffeine is a well-known diuretic, which means that it will send signals to the body that cause more water to be lost via the kidneys and essentially dehydrate the body further. A combination of the water lost due to both caffeine as well as perspiration could in turn put the body at risk of severe dehydration. Sports drinks, on the other hand, are designed with the specific idea of rehydration in mind, hence their composition of carbohydrates and electrolytes makes these suitable to be consumed during physical activity.

Different types of sports drinks

That said, the world of sports drinks is quite a bit more complicated than what has already been mentioned. Although ‘rehydration’ is usually the key term in this area, the real term to pay attention to in terms of the scientific process behind how sports drinks work is actually ‘tonicity’.  

In layman’s terms, the tonicity of a solution is very essentially its concentration, which in this case refers to the ability of said solution to make water move in or out of another solution, which in this case normally refers to human blood. The concentration of human blood ranges around 285 to 295mOsm/kg, and the different categories of sports drinks in this article are formulated around this fact and principle.

The first kind, isotonic sports drinks, are of similar concentration to blood, and comprise a high proportion, around 6% to 8%, of carbohydrates. Experts advise that the consumption of isotonic sports drinks be concentrated during physical activity that is of high intensity and short duration, as this is when a large amount of carbohydrates and energy is required by the body[vii], but without stripping the body of the necessary hydration. Most traditional sports drinks like Gatorade[viii] and 100 Plus[ix] fall under this is the category.

The next category is that of hypotonic sports drinks, which are lower in concentration, or more diluted than blood, meaning that the fluid component of the drinks will be absorbed into the blood the most quickly, ensuring faster rehydration, but the trade-off is that there will be much less energy provided by these as a result. These will generally contain a relatively lower concentration of less than 6% of carbohydrates⁷, hence are not suitable for strenuous physical activity where a lot of energy is required, but should instead be used when rapid rehydration is the objective. Good examples of hypotonic sports drinks include Australian sports drink brand Mizone Sport[x], which boasts hydration that is faster than traditional isotonic sports drinks’, and coconut water.

Hypertonic sports drinks are the category that is most likely to be confused with energy drinks, as their main function also relates to rapid energy delivery. It bears highlighting once again though that caffeine plays no part in the energy provision by hypertonic sports drinks, but instead comes from the carbohydrates in these, which are present at higher levels than the previous two categories, usually above 10%[xi]. This makes hypertonic sports drinks more concentrated than blood, which then helps to deliver large quantities of calories into the bloodstream, thus aids in providing fuel for high intensity activities. As such, this of course means that hypertonic sports drinks should only be consumed when energy is the priority instead of hydration, such as during the recovery and replenishment period after physical exertion¹². Overlooking this can be dangerous, as overly large quantities could dehydrate the system if mistakenly consumed. Hypertonic sports drinks are relatively rarer than the rest, and normally sold as powders[xii], but common, everyday examples include fruit juices and milk. 

Concerns and challenges

THE MAJOR issue experts have with sports drinks tend to border on the amounts of calories they contain due to their sugar levels. As an example, Gatorade contains 21 grams of sugar in every 12oz bottle, which translates to roughly 80 calories per bottle. In countries like Malaysia, Gatorade is normally sold in 500ml (16.9oz) bottles, which means the calorie count is even higher. This may not sound like a terrifying number, but combined with the common misconceptions mentioned in this report, it is a worrying number. Add that to research showing that the consumption of sports drinks is increasing in children and adolescents, many of whom are not athletes and are just aiming to improve the palatability of their regular beverage[xiii], there is a clear reason why this concern will continue to spread amongst experts and consumers, unless a solution can be derived.

A market with huge potential

The global sports drinks market still shows enormous potential, reaching USD 4.62 billion in 2016, and estimated to reach USD 5.92 billion by 2021[xiv]. That said, it may be best for players to attempt to address growing calorie concerns voiced by consumer groups, as some big players have done (Low-calorie G2 by Gatorade[xv], 100 Plus Zero Sugar[xvi]). The other thing to focus on here is of course awareness, so as to ensure that the right sports drink is consumed at the right time so as to avoid any possible future mishaps, as well as to coach the general public that there is in fact no one sports drink for one’s active lifestyle.