Identification of beliefs and food practices related
to performance in endurance and strength athletes
Identificação das crenças e práticas alimentares relacionadas ao desempenho esportivo em atletas de endurance e força
Identificación de las creencias y prácticas alimenticias relacionadas con el rendimiento deportivo y atletas de resistencia y fuerza
*Nutritionist, graduated at the Universidade Federal de São Paulo - UNIFESP
**Professor, Departamento de Ciências do Movimento Humano
Universidade Federal de São Paulo – UNIFESP
Susana Hisamitsu de Oliva*
Claudia Ridel Juzwiak**
This cross-sectional study aimed to investigate eating practices and food beliefs of male triathletes (n=12) and bodybuilders (n=12). Both groups include or exclude certain foods from their diet aiming to improve performance. Bodybuilders overvalue protein foods and low-glycemic index carbohydrate sources, while triathletes value carbohydrate sources. In both groups, high-fat foods and simple sugars are the most commonly excluded items. No association was found between number of beliefs and socioeconomic status (p=0.612), education level (p=0.659), age (r=0.088, CI:0.327-0.475) and the fact that they were counseled or not by a nutritionist (p=0.625). This knowledge enables nutritionists to understand food selection context and to choose more appropriated counseling/educational approaches.
Keywords: Eating habits. Nutrition. Sports. Triathlon. Bodybuilding.
Este estudo transversal teve como objetivo investigar as práticas e crenças alimentares de triatletas (n=12) e fisiculturistas (n=12) do sexo masculino. Ambos os grupos incluem ou excluem determinados alimentos com objetivo de melhorar o desempenho. Fisiculturistas supervalorizam alimentos proteicos e carboidratos com baixo índice glicêmico, enquanto triatletas valorizam fontes de carboidratos. Nos dois grupos alimentos ricos em gordura e açúcares simples são os itens excluídos mais comumente. Não se encontrou associação entre o número de crenças e status socioeconômico (p=0,612), escolaridade (P=0,659), idade (r=0,088; IC:0,327-0,475) ou ao fato de serem orientados ou a não por nutricionista (p=0,625). Estes achados permitem que nutricionistas compreendam o contexto das escolhas alimentares e escolham estratégias mais apropriadas de orientação/educação alimentar e nutricional.
Unitermos: Hábito alimentar. Nutrição. Esporte. Triatlon. Fisiculturismo.
|EFDeportes.com, Revista Digital. Buenos Aires - Año 18 - Nº 182 - Julio de 2013. http://www.efdeportes.com/||
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As early as 500 B.C. athletes were known to adopt “magical” behaviors aiming to improve their performance, among them, diet manipulation and the use of substances with possible ergogenic effects1,2.
The available sports nutrition state-of-the art is translated into guidelines that contribute to optimize athletic results3,4; however, many dietary surveys indicate that athletes consume unbalanced diets, independent of age, sex, sport or nationality5,6,7,8.
Food selection and dietary practices are complex processes involving several factors that include biological (i.e. taste preferences/dislikes, hunger/satiety mechanism), economic (i.e. food availability, prices), psychological (i.e. perceptions, experiences with food), and social-cultural (i.e. model and family/peers influences, beliefs, social norms) issues, which reflect the interaction of the individual with the environment9,10. This interaction over an individual´s life, shape the thoughts, beliefs and food selection, creating a personal system11,12.
The quest for a “winning advantage” leads athletes to consume supplements, certain foods and dietary patterns, regardless of the lack of scientific evidence and adverse effects that they may produce13,14. Also, the belief of potential prejudice attributed to food can lead to its regular avoidance and become a food taboo15 serving as a symbol of a group that is resistant to change11.
How athletes´ food beliefs, traditions and values are understood by the multidisciplinary team working with them will influence their receptivity and adhesion to nutritional counseling enhancing intervention success11. Therefore, the objectives of this study were to understand the prevalence of supplements use in this sample, if athletes include or exclude specific food that they believe will affect their performance and the reasons for that, as well as if strength and endurance sports present distinct food practices and beliefs.
This cross-sectional study was approved by the Ethics and Research Committee of the Federal University of São Paulo (0614/10), and an informed and written consent was obtained from all volunteers prior to data collection.
Male triathletes (n=12) and bodybuilders (n=12) regularly training and competing in the previous 12 months were asked to list foods, beverages and supplements they included or excluded from their diet because they believed them to affect their performance and explain why. These sports were chosen considering their different physiological demands. Athletes´ answers were reproduced as expressed by the athletes and a letter (T=triathletes, B=bodybuilders) and a number was used to identify each subject´s response. Athletes auto-rated their answers on a five-point Liekert scale (1=strongly disagree/5=strongly agree) on nine misconceptions about general sports nutrition issues, adapted from other studies16,17,18. A last statement (10th) was specific for triathletes or bodybuilders.
Student´s t test was used to verify differences between sports and between athletes guided by nutritionists or not, regarding number of beliefs, supplements consumed, sources of information consulted. ANOVA with a fixed factor was used to verify the association between number of beliefs and socioeconomic status and schooling. Pearson´s correlation coefficient was used to verify the correlation between age and number of beliefs. Statistics analysis was performed using the “R” software and a p<0.05 was considered as statistically significant.
The demographic characteristics of the 24 responding athletes are shown in Table 1.
Table 1. Demographic characteristics of bodybuilders and triathletes
Of the 63% athletes who completed college education, 60% held a physical education certificate, and 54% worked as coaches.
With the exception of two triathletes, all others informed that they obtained information on nutrition on a regular basis, from different sources (Figure 1). Bodybuilders listed a significant (p=0.016) greater number of sources (3.3±1.4) than triathletes (1.9±1.2). Professionals consulted as sources were registered dietitians (60%), medical doctors (20%), and coaches (20%).
Figure 1. Nutrition sources of information (more than one possible answer)
Most triathletes received nutrition counseling from registered dietitians; in contrast to bodybuilders, who referred to rely on their own knowledge (58%) to select their diet (Figure 2).
Figure 2. Distribution of athlete according to counseling on nutrition (more than one possible answer)
With the exception of two triathletes, all athletes believed that supplements were essential to improve performance and consumed them regularly (at least 3 times/week). Bodybuilders consumed a significant (p=0.045) greater number of supplements/day (3.8 ± 2.1) than triathletes (2.5 ± 1.2). Table 2. summarizes the supplements consumed and the reasons for their intake.
Table 2. Supplements use and reasons for intake
Ribose, creatine, salt capsules, arginine and vitamina E were also mentioned by 8% of the athletes each, but no reason to justify the use was forwarded.
Tables 3 and 4 summarize foods, beverages and supplements that are included (83% of athletes) or excluded (71% of athletes) from their diets because athletes believe they may affect their performance, as well as the reasons for these practices.
Table 3. Foods, beverages and supplements athletes include because they believe may help them achieve their performance goals
Table 4. Foods, beverages and supplements athletes exclude because they believe may help them achieve their performance goals
Table 5 shows the beliefs for which at least 50% of the athletes “agreed”/“strongly “agreed”.
Tabela 5. Statemens on sports nutrition (beliefs) for which at least 50% of athletes “agreed” or “strongly agreed”
Triathletes agreed to 4.1±2.5 beliefs, while bodybuilders agreed to 5.9±2.2 (p=0,067). No association was found between number of beliefs and schooling (p=0.659), socioeconomic status (p=0.612), being counseled by a registered dietitian (p=0.625) or age (r=0.088; IC95% -0.327; 0.475)
Differences in supplement intake (number and type) and food practices may be related to the different sports physiological demands, information sources and professional counseling.
Different from other study19, most triathletes (75%) receive guidance from nutritionists. Even when having accesses to nutritionists, supplement intake is influenced by other professionals or self-prescribed17,20 Studies which have investigated nutrition knowledge of coaches identified some misconceptions21,22, disparity between knowledge and practice or lack of assurance17,18,21. It is important that nutritionists step up to a stronger role in providing nutritional counseling to athletes and in providing coaches and trainer with accurate nutrition information.
Books, internet and non-technical magazines were also listed as nutrition sources. Studies have been showing aggressive advertising strategies to promote supplement intake by both elite and recreational athletes, especially bodybuilders23,24. Popular non-technical magazines and internet sites stimulate supplement use by overvaluing muscle size as a representation of masculinity and social power25,26. Also, information provided can be inaccurate and incomplete, particularly on claim and safety issues27,28,29.
Supplement use is a common practice among athletes of different level, sports, gender, age, and nationality20,30,31,32,33,34,35. Our findings are in accordance to the literature as all male athletes studied referred a regular intake of supplements. Some of their choices may reflect beliefs, as a result from ignorance or from commercial and economic biased publicity36. Dascombe et al30 also identified different patterns of supplement use among athletes from different sports and suggested that the range of marketed supplements and marketing strategies differ between sporting cultures and may explain this finding.
Some misconceptions were found regarding some possible effects listed by the athletes. The attraction to protein/amino acids supplements may be relate to the association of its intake and the construct of a muscular body25,37 and the implicit promise that “if I eat more, more body protein I will build”37. Most triathletes (83%) reported taking carbohydrate supplements during and/or after exercise which is in accordance to other study38 and the reasons given agree with sports nutrition guidelines3,4.
Athletes should be aware of the evidence-based results of investigations on the subject as for many supplements, even when theoretical rationale is sound, more research is still necessary (i.e. BCAA), while some have been shown to be ineffective (i.e. glutamine) or insufficient research is available4. Furthermore, athletes place themselves at a higher risk of positive doping due to the presence of non-declared prohibited substances40.
Studies on bodybuilders´ and triathletes´ nutritional practices have been showing different patterns between these groups7,37,38,41,42. While some food beliefs are based on the results of scientific research, frequently they reflect athletes´ inaccurate interpretation of research facts36. Bodybuilders indicated more beliefs than triathletes, some similar to the findings of other studies26,37.
Triathletes listed sport drinks and carbohydrate sources as choices aiming to achieve their athletic goals. Burke et al43 also found triathletes to be aware of the importance of carbohydrates intake for their performance.
With the main objective to increase muscle mass and reduce body fat, bodybuilders usually adopt a protein-rich diet with low energy content42,44. In this study it was possible to identify a preference for some protein sources (egg whites, breast chicken, whey protein) because of their high protein, low-fat and low-energy content. Sabino et al37 also described bodybuilders’ preference towards “white foods”, which are rich sources of protein or carbohydrates, such as chicken breast, fish, pasta (without sauce or salt), potato, banana, and egg white. In their study athletes attributed to these foods the ability to “grow muscles” and considered them as essential foods, almost sacred. White meat was referred to as “clean” food, which won’t increase body weight37. Choosing protein foods is related to one of the laws of magical thinking, “similarity”9, based on the principle that “likes make like”14. Also, bodybuilders listed low-glycemic index (GI) carbohydrate sources (sweet-potato, oat bran, brown rice, pumpkin) but did not forward an explanation of the relationship between GI and a possible effect on performance or athletic goal achievement. Bodybuilders studied by Sabino et al37 also attributed to whole foods (pasta and rice) the power to “make grow”. Restricting carbohydrate options may lead to monotonous diet, as in the case of a bodybuilder, who referred eating only sweet-potatoes as carbohydrate-source.
Of the few foods athletes refer to exclude, both groups listed fat, fried, sugar-rich options. Sabino et al37 also found bodybuilders to avoid fatty and fried foods, as well as fast foods, aiming to achieve “beauty, health, purity and strength”. Three (27%) bodybuilders exclude milk from their diet because they believe that lactose has a “deleterious effect on muscle definition”. Also, the majority of bodybuilders (75%) agreed completely/agreed with this misconception.
Agreement to the beliefs on protein (Table 5.) is in accordance to what athletes reported as practice. Both bodybuilders and triathletes reinforced the idea of an overvaluation of protein foods/supplements, as well as misconceptions, which are reported in other studies39,45.
This study presents many limitations - because of the size and type of the sample the results cannot be considered representative. Also, the use of other qualitative methodologies should improve the quality of responses (i.e. focus groups, in depth interviews). Even so, we were able to identify that bodybuilders and triathletes reported to believe in different foods and supplements as important factors to achieve their competitive objectives. Both groups attributed especial value to some of them, which reflected beliefs and some misconceptions that may lead to restricted and unbalanced diets. If beliefs lead to the adoption of behaviors that are discordant from sports nutrition guidelines, athletes may experience no benefits on performance or be prone to deleterious effects. Furthermore, beliefs create strong barriers to behavior change and pose a great challenge to nutritionists. Understanding beliefs and their specificity according to sport is an important strategy to develop custom-designed nutrition education programs that will elucidate these issues, affecting the meaning attributed to food and supplements and enabling athletes to build a food selection pattern more adequate to maintain their health and improve performance.
The study demonstrated bodybuilders and triathletes present different beliefs on supplementation and food practices. To understand these beliefs and to recognize misconceptions is important because it enables nutrition professionals to go beyond “teaching what is right about nutrition”, but to be able to understand food selection context and what is recognized and valued by a social group, bringing the practice nearer to what is considered as ideal by state-of-art sports nutrition guidelines.
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We thank the contributions of Eunice Nakamura, Aleksander Juzwiak and Fábio Tadeu Montesano.
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