Sports Drinks

A necessary component for the proper hydration of your runners or a cleverly marketed bottle of sugary water? This article explores the science behind modern sports drinks and the role they serve for the modern athlete.

You've probably heard of the role sports drinks play in replenishing electrolytes - but what exactly does this mean?

Electrolytes refer to a chemical substance that produce an electrically conducting solution when dissolved in water. The reason they are so important for the human body is that many of our key functions such as the regulation of our heartbeat, blood pressure, cellular hydration, muscle contraction and tissue regeneration are reliant on the electrolytes in our bodily fluids to occur. For example, it is the electrolytes in our body that carry the electrical signals across a cell and into neighbouring cells to promote muscle contractions and nerve impulses.

When it comes to exercise, loss of sodium ions through sweating is considered the biggest challenge that runners and athletes face. Sodium is required for muscle contractions, nerve signalling and plays a role in maintaining a healthy fluid balance across our cells. An athlete suffering from a lack of sodium may notice muscle weakness, cramping, numbness, decreased awareness and in severe cases blood pressure changes, heart problems and seizures. Coaches need to be aware of these symptoms and adjust the intensity, duration or end the training session early to prevent symptoms from worsening.

Water alone will not replenish electrolytes and sports drinks are considered by the American College of Sports Medicine as a viable method of rectifying electrolyte deficit post-exercise. Evidence suggests that low carbohydrate concentration sports drinks are also effective at improving athletic performance (Coombes & Hamilton, 2012). However, when coaching young athletes it is important to consider whether or not it is beneficial to the individual based on their personal circumstances. Sports nutritionist Mangieri (2017) has no issue with young athletes drinking sports drinks when used appropriately. As a general guideline, Mangieri advises that when exercising for over an hour, a young athlete may benefit from drinking more than water alone. Sports drinks may also be appropriate for athletes that sweat heavily or when exercising in warmer conditions.

There is some opposition to the use of energy drinks from the scientific community that coaches should consider. The first argument against the use of sports drinks comes from a clinical report examining their appropriateness for children and adolescents by the Committee on Nutrition and the Council of Sports Medicine and Fitness (2011). They argue that for the average adolescent, sports drinks contain excessive carbohydrates that may lead to an increased risk of obesity. The report also warns against many sports drinks that contain caffeine or guarana as high doses of these stimulants can negatively affect developing neurological and cardiovascular systems. There is also the risk of addiction, leading to a reliance on these stimulants for the individual’s normal functioning. Finally, it is argued that the average adolescent’s electrolyte requirements are met sufficiently by a healthy balanced diet and therefore sports drinks offer little or no advantage over plain water. However, it should be noted that the authors explicitly state that young athletes who participate regularly in endurance or high-intensity sports are beyond the scope of the report and may have additional electrolyte and energy demands that the average adolescent does not have.

Coaches should also be aware of the effect sports drinks may have on their athlete’s dental health. Laboratory experiments have demonstrated the potential for acidic drinks, such as most popular sports drinks, to erode enamel and lead to a general deterioration of dental health (Rees, Loyn & McAndrew, 2005). However, studies conducted amongst the population of competitive athletes have shown no significant difference in dental health between sports drinks consumers and a control group (Milosevic, Kelly & McLean, 1997). Nevertheless, the study does warn that the erosive potential of acidic drinks is real and that additional consideration must be given of the effects over a longer period, especially for younger athletes.

WHAT THE EXPERTS ARE SAYING

“If used properly, sport drinks can be very beneficial” Heather R. Mangieri, 2017

“Sports drinks should be trialled during training rather than competition” Sports Dietitians Australia, 2017

“Caffeine and other stimulant substances contained in energy drinks have no place in the diet of children and adolescents.” Schneider & Benjamin, 2011

“There is evidence to suggest that consuming a sports drink will improve performance compared with consuming a placebo beverage” Coombes & Hamilton, 2012

What should you do if you suspect your athlete has an electrolyte imbalance?

The first step is to refer your athlete to their primary care practitioner. The most common correction for an electrolyte imbalance will be a change to the athlete's diet and hydration. In severe cases a practitioner may recommend supplements.