The study appears to be among the first of its kind to take an epistemological approach to how athletes make supplementation decisions. In other words, the researchers tried to parse out what the athletes think they know and how they know these things.
The study was published recently in the Journal of the International Society of Sports Nutrition. The authors, who are associated with institutions in Croatia, Italy, Kosovo and Slovenia, said the issue of how athletes gather information about supplements and decide which of them to use has been understudied.
For the study they recruited 912 professional athletes, 356 of whom were women, from four Olympic sports: basketball, handball, soccer and volleyball. They used questionnaires to determine the levels of subjective knowledge (how much the athletes thought they knew) and objective knowledge about supplements and nutrition. They also assessed actual dietary supplement usage as well as what sources of information athletes use to decide which products to take.
Risk of being led astray
The authors noted that dietary supplement usage by athletes is high across the board. While these supplements are often chosen for legitimate nutritional reasons, they noted there is a risk that ill informed athletes could be led astray by products that make splashy claims that might also include dodgy ingredients.
“It is generally accepted that athletes consume DSs to improve their recovery and performance and/or to overcome the lack of certain nutrients for specific reasons (i.e., vegetarianism, female athletes during their menstrual cycle). However, due to the competitive spirit of sports, athletes are particularly vulnerable to aggressive DS marketing. Although most dietary supplements are produced and distributed in a proper way, inaccurate labeling of ingredients and lack of evaluation from regulatory agencies are known to be a problem, which sometimes leads to negative health consequences and even positive findings on doping substances,” they wrote.
Players think they know more than they actually do
The results from the questionnaires showed that there was a poor correlation between subjective knowledge and objective knowledge. The objective questionnaire consisted of 10 true or false statements, such as “Dark yellow urine is an indicator of proper hydration of the body” and “Large chains of amino acids form carbohydrates.” The subjective questionnaire asked the athletes to rate their knowledge from none to good/very good.
The researchers also sought to categorize the athletes according to their experience and achievement, using such measures as having taken part in a championship competition or having been chosen for a national team. They found that dietary supplement usage tended to decline as the athletes became more experienced and successful. The authors noted this declining supplement usage with experience and achievement has been documented in other sports (sailing and rugby) from the similar area of Southeastern Europe. No reason for this was postulated.
Self education most prevalent
The study also looked at where athletes were getting their information. About a third said they had no knowledge. For those who claimed to know something about supplements, they were about twice as likely to say they had gathered their information themselves from books, magazines and things they had read online, as opposed to relying on formal education or information they had received from coaches.
Given the poor correlation between what the athletes thought they knew as opposed to their measured knowledge, the researchers said there is a need for more structured education on nutrition and the role dietary supplements can play.
“There is a clear risk for inappropriate usage of DSs, especially with regard to the fact that the majority of studied athletes declared ‘self-education’ as the primary source of information on nutrition and DS,” they concluded.
Source: Journal of the International Society of Sports Nutrition
What drives athletes toward dietary supplement use: objective knowledge or self-perceived competence? Cross-sectional analysis of professional team-sport players from Southeastern Europe during the competitive season
2019 16:25 https://doi.org/10.1186/s12970-019-0292-9
Authors: Sekulic D, et al.