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Dose Matters – Sports psychologists are looking for ways to curb the rising consumption of nutritional supplements for athletes

Doping or sports supplements. Photo: fotolia.com/goldencow images.

Doping or sports supplements. Photo: fotolia.com/goldencow images.

They are available as capsules, lozenges, tablets, and liquids: supplements are sold by every drugstore and gym these days and from many online stores. And yet, these products that are supposed to supplement our diets are not without controversy. Certain groups may even be harmed by their unregulated use – such as athletes, particularly in professional and competitive youth sports. Organizations like the International Olympic Committee, the World Anti-Doping Agency, and the National Anti Doping Agency Germany, therefore, advise against taking unnecessary substances, which are suspected of being a gateway to doping. All too often, though, these appeals go unheard. Consumption figures are spiking. In their current project, sports psychologists at the University of Potsdam are looking at how to curb supplement consumption. At the conclusion of the project, the researchers will be presenting evidence-based proposals on how to prevent misuse.

A study participant, who is about 14 years old, sits in front of a computer. He focuses on the screen – but there is hardly anything to see. Only if you watch very carefully will you catch anything. An assistant of project head Prof. Dr. Ralf Brand presents visual stimuli: words like “performance” or “health”. They appear only for seven milliseconds, which falls below the human perception threshold, so he is not able to read them, let alone contextualize them. Nevertheless, what the test subject is not even really able to see significantly influences how quickly he reacts to words displayed for slightly longer, namely two seconds. It happens automatically. For example, he decides very quickly that “creatine” is a popular sports supplement after having been shown the word “performance”. The overall results of the test series indicate that it would have taken fractions of a second longer had the word “health” been presented to him. To a layperson, this experiment may seem unusual, but this is a standard cognitive scientific method of investigating how the human brain processes information.

The test series has since been completed, and Brand and his fellow researchers are now able to answer one of the project’s central questions: Why do athletes so often resort to nutritional supplements? What drives them, and what objectives are associated with taking them? The project team ruled out conventional interview techniques as its research method. “Athletes are aware that they should not be taking nutritional supplements,” Brand explains, “so interviews will produce biased results; they will say what is expected.”

The role of the unconscious in decision making

The researchers instead opted for an implicit, reaction-time-based method in order to get conclusive results. This decision turned out to be a good one, since they were able to find out more about the role of the unconscious in human thinking. They based their research on what psychologists refer to as goal systems theory. According to this theory, behavior is largely goal-driven whenever goals are automatically associated with evaluations, product presentation, and action patterns. “In our project, we assumed that athletes unconsciously and automatically have certain associations when it comes to supplements,” the Professor explains, “and the strength of these associations may influence their actions.”

The laboratory experiments have so far corroborated this. Their outcome has been both unambiguous and surprising: The approximately 80 participating athletes linked nutritional supplements with the goal of performance enhancement, which is cognitively distinguishable and very strongly represented mentally. You can tell this from the reactions of the athletes who revealed – under immense time pressure and completely subconsciously – their associations with the respective stimuli. Health was much less associated with nutritional supplements, which contradicts earlier studies by psychologists who evaluated completed questionnaires.

So what is behind the test that may seem so unusual to non-experts? It is a remarkable process: The stimulus that appears on the screen – a word presented for mere milliseconds – is detected on the retina at light speed. From there, the information is transmitted through the optic nerve directly to the brain. Since it is present for such a short time, it escapes our attention. It cannot be consciously perceived, yet the brain still reacts, creating associations that are automatically and completely unregistered.

The unconscious is always present. Not every piece of information that enters our brain is perceived. The brain takes in much more than we notice. Traces of it are found in automatic cognitions – a process referred to as priming.

Many athletes use nutritional supplements despite a wealth of information on potential risk

All of this will hardly interest young competitive athletes. Their daily schedules are tight. Parents, teachers, coaches, and officials place intense pressure on them. To meet these expectations and enhance their performance, many take nutritional supplements specifically made for athletes. According to a 2012 nationwide survey from the Federal Institute of Sports Science, 90% of the 1,138 athletes on the German Olympic Sports Confederation roster took supplements at least once a month; nearly 27% did so on a daily basis, and 76% of these athletes took two or more products at the same time. “Protein shakes, vitamin and mineral preparations, but also substances like creatine are very popular,” Brand says. This could be problematic, if not dangerous, for competitive athletes, since overdosing poses health risks. Experts find that incorrect dosing of creatine can lead to cramps, too much magnesium to considerable digestive disorders, and large amounts of zinc to an increased risk of developing cancer. Specially trained nutritionists have been visiting Brandenburg’s elite sports schools since 2009 to inform 7th-10th graders about these and other facts, yet with little success, as shown in a study by Brand and his colleagues Albrecht Hummel from Chemnitz and Thomas Borchert from Leipzig. Between 2008 and 2012, the three professors annually interviewed more than 1,000 students at sports schools. The 14-16 year olds were asked about everyday life as well as psychological and educational experiences. It turned out that in some disciplines (triathlon, weightlifting), more than half of the respondents regularly consumed nutritional supplements, whereas in most other sports (including soccer, canoe racing, swimming) it was 33%. “Here social norms play a major role,” the sports psychologist underlines. They suggest that success can be more easily achieved with the help of nutritional supplements, and “practically everyone” in competitive sports is using them. The fact that many everyday norms go unspoken – including those guiding our behavior – may explain their prevalence. “This was one of the reasons why our implicit approach was so important.”

Not all products sold online are safe

There are not enough role models yet to counteract the trend of haphazardly taking nutritional supplements. After all, their reasonable consumption under proper supervision may well be healthy. “This, however, is not true for all nutritional supplements, and the effect differs from athlete to athlete and from situation to situation,” Brand says. “So advertising for such products should not focus on performance enhancement, but on health aspects. Ideally, this would one day lead to more prudent use.”

A very hot topic linked with nutritional supplements is doping: There have been cases of German athletes unintentionally taking nutritional supplements containing substances banned by the World Anti-Doping Agency. Such incidents were avoidable. The Centre for Preventive Doping Research at the German Sport University Cologne publishes an online list (“Kölner Liste”) of uncontaminated products, which have been tested for anabolic and androgenic steroids (prohormones) and stimulants. This is very helpful, especially for young athletes who prefer buying nutritional supplements online, where cheap, contaminated products constantly surface, according to research in England. “Of course, not everybody who regularly uses nutritional supplements graduates to banned substances,” Brand concedes. “On the other hand, we know of no athlete who has doped that did not take nutritional supplements.” There is, however, no empirical evidence that taking nutritional supplements in fact leads to using banned substances.

In his work on the increased consumption of nutritional supplements by young athletes, Brand relies on goal systems theory and implicit measuring. This fits seamlessly into the research program of cognitive scientists at universities exploring fundamental cognitive processes. The central question is how our brain processes information consciously and subconsciously. “Our latest research on nutritional supplements in competitive sports,” Brand concludes, “has yet again demonstrated how complex, yet examinable these processes are.”

The Researchers

Prof. Dr. Ralf Brand holds a degree in psychology and is a certified teacher of physical education and English. He completed his Ph.D. in Konstanz in 2001 and habilitated in Stuttgart in 2006. He has been Professor of Sport Psychology at the University of Potsdam since 2008.


Universität Potsdam
Strukturbereich Kognitionswissenschaften
Am Neuen Palais 10, 14469 Potsdam
E-Mail: ralf.brand@uni-potsdam.nomorespam.de

Franz Baumgarten studied psychology at the University of Potsdam. He joined the division of Sport and Exercise Psychology of the University of Potsdam in 2013 as a research assistant.


E-Mail: frabaumg@uni-potsdam.nomorespam.de

The Project

Nutritional supplements for athletes: An experimental approach to explaining, predicting, and preventing the consumption of critical substances by young athletes in competitive sports based on goal systems theory
(„Nahrungsergänzungsmittel im Sport. Ein experimenteller Zugang zur Erklärung, Vorhersage und Prävention des Konsums von kritischen Substanzen im Nachwuchsleistungssport mit Hilfe der Theorie der Zielsysteme“)
Head: Prof. Dr. Ralf Brand
Duration: January 2015–December 2016
Funded by: Federal Institute of Sports Science (BiSp)

Text: Petra Görlich
Online-Editing: Agnes Bressa
Contact Us: onlineredaktion@uni-potsdam.nomorespam.de