Introduction
Eating disorders (EDs) cover a range of abnormal eating or weight control practices. These include excessive exercising, the restriction of dietary intake to minimize energy intake, binging with or without purging, as well as abnormal body dissatisfaction (3). Both male and female athletes are at risk of an ED due to the demands of the sport and potentially negative comments made by teammates, coaches and supporters on their body type and performance (14). In addition, the risk for disordered eating among athletes may be further heightened by personality traits commonly seen in athletes such as determination, perfectionism, and obsession in pursuit of their quest to obtain their desired body composition (11). Unfortunately, disordered eating can put the athlete at risk of health issues such as impaired cardiovascular function, kidney disorders, low energy availability, electrolyte disturbance, and nutrient deficiencies, as well as decreased athletic performance (25). Furthermore, there seems to be an association between body image dissatisfaction and EDs among elite athletes (16,24). In elite male university athletes, body image dissatisfaction and drive for muscularity were both associated with negative psychological states and bulimic symptoms (13,28). Others have shown that in a variety of sports, elite male athletes with body image dissatisfaction also show signs of disordered eating behaviors (18,27).
Previous research has suggested that around 21.2% of a male athletes report behaviors associated with an ED (34), although a lower prevalence has been reported for weekly binge eating (13.02%) and purging (5.52%), which included laxative abuse, exercising excessively, or vomiting (19). Sundgot-Borgen and Torstveit (38) also reported that the prevalence of subclinical or clinical EDs in athletes was ∼13% (13.5%), which is higher than seen in controls (4.6%; p < 0.001). They did, however, highlight differences between sports. For example, the prevalence in ball sports was 5% but was higher in other sports categories such as “antigravity” sports (e.g., high jump) where the prevalence was 22% (38).
Not only does the type of sport played seem to influence the prevalence of EDs, so too do age and competition level (30). Eating disorders generally develop during adolescence or during transitional phases in life (21) with others suggesting that those aged between 18 and 26 years are at greatest susceptibility for an ED (30). For athletes, this could be the transition into the professional sporting environment. It is, therefore, possible that younger players are more likely to show signs of poor body image and disordered eating compared with their more experienced teammates, especially during preseason. Indeed, life stresses such as changing environment and becoming more independent have been reported as increasing the risk of the development of an ED (30). For many, the preseason is their first exposure to the professional sporting environment and its associated nutritional support. This may, therefore, be a time of increased stress among these players because they strive to impress coaches and more established members of the team. Importantly, it has been shown that among adolescents, stress is a significant contributor to poor body image (26).
Before a rugby union competitive season, a preseason training period is used by athletes to make improvements in strength, conditioning, and body composition toward desired ideals for their playing positions (1,5). Rugby union players can be broadly grouped by their playing positions into endomorphic-mesomorph “forwards” and more balanced-mesomorph “backs” (31). Dietary energy requirements are substantial during the preseason period because of high exercise energy expenditures plus energy and protein requirements for building lean muscle mass (5). However, negative body image may impact on eating behaviors during this critical time and compromise training adaptations. The Eating Disorder Inventory (EDI) questionnaire not only indicates disordered eating and ED “risk,” but specifically, the 7-item “drive for thinness (DT)” and 9-item “body dissatisfaction (BD)” subscales can also be used as a measure of body image.
At present, there are few studies that have investigated EDs among elite male rugby players and further, no study has investigated the relationship between body image and eating behavior in these athletes. This study aims to investigate the relationships between EDs, body image, and age in elite rugby union players during their preseason training period.
Methods
Experimental Approach to the Problem
Using a cross-sectional study design, participants were recruited from 1 New Zealand Super Rugby franchise during the first week of preseason training (November, 2014).
Subjects
All participants provided written informed consent before undertaking the study. Ethical approval for this study was granted by the University of Otago Human Ethics Committee.
Participant characteristics are presented in Table 1. A total of 26 participants were eligible for the study and completed the body image questionnaire and body composition measures. Broadly divided by their playing positions, there were 18 forwards and 8 backs. Participants were all older than 18 years (range 19–28 years), body mass ranged from 76.3 to 144.1 kg, and sum of 8 skinfolds from 49.1 to 151.2 mm.
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Table 1.: Mean ± SD baseline demographic information for all the participants, forwards, and backs.*†
Procedures
Anthropometry
Body mass was measured using a Tanita BWB-800 MA scale, (Tanita, Tokyo, Japan) with the mean body mass calculated from measurements taken on the first morning of 3 consecutive days of preseason training.
The team dietitian (International Society for the Advancement of Kinanthropometry level 1 accredited) measured participants' skinfolds from 8 sites (triceps, subscapular, biceps, iliac crest, supraspinale, abdominal, thigh, and medial calf) over the first 2 days of preseason training and the sum of 8 skinfolds (S8SF) was calculated. Body density was estimated using the sum of 4 skinfolds (triceps, subscapular, biceps. and iliac crest) and regression equations derived by Durnin and Womersley (9). Participant's percentage body fat was estimated using the Siri equation (36). This was then used to estimate fat-free mass for each player.
Body Image and Eating Behavior Questionnaire
On the first day of preseason training (November 2014), participants completed a 49-item questionnaire on body image and disordered eating behaviors. The questionnaire was developed from the Low Energy Availability Amongst New Zealand Athletes (LEANZA) questionnaire (37), which sourced questions from the EDI-3 questionnaire, described elsewhere (15,23,37).
Briefly the EDI-3 is a self-administered questionnaire assessing ED behaviors and symptoms. It is composed of 3 subscales (a) DT, (b) bulimia (B), and (c) body dissatisfaction. For each subscale, players were classified as having low, medium, or high risk of suffering from an ED. The sum of scores for each individual subscale (DT, B + BD) is then used to derive a T-score to provide an EDI- Risk Composite (EDI-RC) (Garner (15)). For each question, responses were made on a 6-point Likert-type scale with possible responses: “never,” “rarely,” “sometimes,” “often,” “usually,” or “always.” Given that some rugby players need to gain weight during preseason training, the DT questions “I exaggerate or magnify the importance of weight” was changed to “I exaggerate or magnify the importance of my skinfolds” and “I am terrified of gaining weight” was modified to “I am terrified of gaining body fat.” Participants were also asked “Do you think you have gained any weight in the off-season?”, “What is your desired weight?” and “What are your desired skinfolds?”. These were then compared with their measured skinfolds and weight.
Statistical Analyses
Mean and standard deviation (mean ± SD) values were calculated for the participants' characteristics, body image, and subscale scores. All data were checked for normality of distribution using a Shapiro-Wilk test. Differences between forwards and backs for questionnaire data were determined using Mann-Whitney U-tests and all other differences between forwards and backs were determined using independent t tests. All associations with questionnaire data were determined using ordinal logistic regression and all other associations by linear regression. All statistical comparisons were 2 tailed, and p values less than 0.05 were considered statistically significant. Statistical analyses were performed using Stata 12 (StataCorp, College Station, TX, USA).
Results
Playing Position
The forwards were significantly heavier than the backs (p < 0.001) and had higher S8SF (p = 0.0181) (Table 1). However, there was no significant difference between the forwards and backs for the difference between their actual and desired S8SF, either absolute (kilogram) (p = 0.966) or relative (%) (p = 0.502).
There were no significant differences in any of the EDI-3 subscales (DT, B, and BD) or EDI-3 total score (all p > 0.05) between forwards and backs (Table 2).
Table 2.: Body image scores (mean ± SD [range]) derived from the EDI for all the participants, forwards, and backs.*†
Body Image Scores
Mean ± SD for “DT,” “B,” “body dissatisfaction,” and “total score” are shown in Table 2. The highest scores on the DT and body dissatisfaction scales were 17/28 and 25/40 respectively, compared with a highest score of 3/32 on the bulimia scale. The highest total score (B + BD + DT) was 29/100. Eight (30%) players were classified as being at medium risk for an ED (1 based on their DT score and 7 on their body dissatisfaction score).
Eating Behavior Responses
Sixty-two percent of participants reported that they never went on eating binges “where they felt they could not stop,” whereas 42% reported “they had never binged in the previous 3 months.” Binge eating at least once a week was reported by 15% (n = 4/26) of participants. Three of these 4 players reported “never” or “rarely” feeling out of control during a binge eating episode. However, of the 4 participants, 1 reported pathological weight control measures 2–6 times a week and another “sometimes” thought about vomiting to try and control body weight and skinfold measurements. The regularity of binge eating episodes in the past 3 months was positively associated with body dissatisfaction (p = 0.013).
More than 3 quarters (77%, 20/26) of the participants reported “avoiding certain types of food.” Six participants (23%) reported that “there are no foods that they avoid.” None of the participants reported following special diets such as vegetarian, vegan, or gluten-free. Of the food-avoiding participants, 40% (8/20) reported “avoiding certain foods” because they believed that they were “bad for their health,” 30% (6/20) “avoided foods to prevent increases in fat mass and skinfolds,” and 10% (2/20) to “avoid gaining weight.” Other reported reasons were “don't like those types of food” (15%; 3/20), “want to stay in shape” (5%; 1/20), “empty calories” (5%; 1/20), “not part of diet” (5%; 1/20), and “foods are high in fat and sugar” (5%; 1/20).
Off-season weight gain was reported by 69% (18/26) of participants, wheread 31% (8/26) reported that they did not gain weight during the off-season. Of the 18 players who gained weight in the off-season, 12 intentionally gained weight. The main method used to gain weight was gym weights and increasing the amount of food that they were eating, with 4 of the participants stating that they were consuming protein supplements for this purpose. Of the 6 players with unintentional weight gain during the off-season, 4 stated they did so because of “lack of training,” 3 stated that “bad diet” was responsible, and 1 participant stated they “had a few beers.”
Eleven participants (42%) reported previously being told that losing weight would help improve their performance. However, this had no effect on any of their body image scores (“DT,” “B,” “body dissatisfaction,” and “total score,” all p > 0.05).
Body Composition Indices
There was no significant difference between actual and desired body mass (p = 0.401). The range for the difference between actual and desired body mass was −8.33 to +4.23 kg. There was no significant difference between forwards and backs for the difference between actual and desired body mass.
The mean ± SD S8SF was 80.5 ± 29.9 mm with a range of 49.1–157.5 mm. The desired S8SF mean ± SD was 70.3 ± 26.5 mm, ranging from 40.0 to 160.0 mm. This meant that there was a mean difference between actual and desired S8SF of −10 mm (range −61.2 to +95.4 mm), with this difference approaching significance p = 0.064. Five players wanted to increase their S8SF and 3 players had a desired S8SF that was within 1.0 mm of their actual S8SF measure.
Age
There was a significant inverse association between the age of participants and frequency of “stuffing themselves with food” (p = 0.002) and the frequency of emotional eating (p = 0.016). However, there was no difference seen for the frequency that they thought about binge eating (p = 0.591). There was a significant inverse relationship between the bulimia subscale and age (p = 0.034).
Younger players also tended to report that they exaggerated the importance of weight/skinfolds more frequently (p = 0.027). However, no associations between age and percent difference in actual and desired skinfolds was seen (p = 0.181, r = 0.073).
There were no significant differences based on age in the frequency of losing control while eating (p = 0.341) or for any questions from the body dissatisfaction scale (all p > 0.05).
There were no significant associations between age and body dissatisfaction, DT, or total score (all p > 0.05). Reanalysis without the modified questions did not neither affect these associations (p > 0.05), nor were there any significant associations for the difference between the desired body composition measures and actual body composition measures (all p > 0.05).
Discussion
The range of EDI scores in this study indicates that rugby union players are not homogenous in how they subjectively view their body shape. Considerable variations in body image and desired weight change were seen in this study, which is in line with previous research in male athletes including those competing in ball-game sports (2,12). Our results are similar to those previously reported by Martinsen and Sundgot-Borgen (22) who showed that 25% of adolescent athletes were “at risk” of an ED and Torstveit et al. (40) who stated that 46.2% of athletes reported one or more symptoms of disordered eating, of which 27% were diagnosed with an ED. It is interesting that most players in the current study were classed as being “at risk” based on their body dissatisfaction score. Using a 0–3 scoring system, elite track and field athletes reported a DT score of 2.78 ± 4.82 of a maximal 21 and a body dissatisfaction score of 4.13 ± 5.28 of 27 (17). Higher scores were found in elite university volleyball players with 6.57 of 21 and 12.00 of 27 for DT and body dissatisfaction, respectively (12). Body dissatisfaction has also been assessed in elite adolescents competing in esthetic sports. Using a 6-point scoring system, mean body dissatisfaction was reported as 19.7 ± 8.4 out of 54 (23). These studies indicate that male athletes generally do not exhibit a high DT. However because the body dissatisfaction scores tended to be higher with larger variation, it is likely that some male athletes have body image concerns. Indeed, our data suggest that although rugby union players tend to have the tall muscular body shape considered “ideal” by society, their perception of themselves or their perception of their “ideal” is congruent to their actual body composition (4,32,35). However, elite athletes also experience sports-related pressures to maintain ideal body compositions, which can heighten their risk for poor body image and disordered eating behaviors (20). Therefore, their perception of their body may not reflect that of the society.
The prevalence of disordered eating behaviors for individual questions reported in this study is in agreement with previously published values in elite male athletes. Avoiding particular foods is frequent in some athletic populations with 60% of judokas (judo) and 62% of triathletes reporting food avoidance for weight control (7,33), compared with 77% in the current study. Although not intended for weight control, binge eating is another commonly reported disordered behavior in elite male athletes. Elite male university athletes reported similar rates of binge eating to the rugby players in this study (17 vs. 15% in this study) (18), although when divided by sport type, elite university athletes competing in ball sports reported much less binge eating than those competing in other sports (6). Nevertheless, not all athletes who reported binge eating also report feeling out of control during a binge. Thus, the true prevalence of binge eating episodes is likely to be less than that reported. This is consistent with reports in other elite university athletes competing in a variety of sport types (8,21).
Comparatively, the disordered eating behaviors of vomiting, laxative, and diuretic abuse are infrequently reported in elite male athletes (6,29,39). Consequences of these behaviors include dental erosion, electrolyte imbalances, and dehydration, with the latter 2 having the potential to directly impair athletic performance. Thus, it is still concerning that 1 athlete in this study reported regular laxative use and another considered vomiting. The inverse associations between these disordered eating patterns and age may be due to inappropriate nutrition knowledge. Indeed, nutrition knowledge has been shown to be a predictor of disordered eating (27). However, the same pattern was seen with emotional eating, and it may be that the times of emotional eating coincide with the perception of “stuffing” themselves. This may reflect a more unsettled homelife. Although older players are more likely to have a stable homelife and possibly more secure contracts, this may not always be the case for the younger players who may have moved away from home for the first time. Therefore, emotional issues, increased stress, and the transitions occurring in their lives both at training and at home, combined with potentially lower nutrition knowledge and cooking skills, could result in poorer nutritional habits. These factors need to be considered when discussing body composition and nutrition with players; in particular, younger players who may be more susceptible to disordered eating.
Previous research has shown a higher body fat percentage in athletes to be associated with greater body image dissatisfaction (18). However, the current study did not observe any associations between the actual body composition measures and responses to body image questions. This is potentially due to the body composition requirements of rugby compared with other sports, which is characterized by lean backs, with forwards being heavier with more lean mass and fat mass than the backs. In rugby, body composition requirements depend on playing positions. However, because of the low number of participants available for each playing position, it was not possible to determine if associations existed within playing position.
A desired weight loss of −1.4% was found in 7% of elite male university athletes who reported restrictive eating patterns such as chronic dieting and fasting. In comparison, a desired weight change of +4.6% was found in the asymptomatic athletes (18). In male triathletes, of whom 34.9% desired a smaller body shape and 11.8% a larger body shape, only 25.5% meet the 6 minimum recommended servings of the “breads, cereals, and rice” food group (7). In the current study, 21 participants wanted smaller skinfolds and the difference in their desired weight and actual weight ranged from −6.4 to +4.0%, which exceeds the changes desired by the triathletes who were also showing signs of restrictive eating. Triathletes have a lower body weight compared with rugby players, and triathlon is considered an endurance sport compared with the high-intensity high-impact nature of rugby. Therefore, their nutritional requirements and body composition requirements could be substantially different (10). Although no significant associations were seen between desired and actual weight and bulimia scores, it is possible that those participants who desired a large change in body weight or S8SF were engaging in other practices that were not identified in the current study. It is interesting that there was an inverse association between age and both binge eating behaviors and the emphasis that players place on their skinfold measures. This suggests that younger players have a greater focus on body composition, which seems to be linked with poor nutritional practices such as binge eating, which may impact performance and health. This may be due to a lack of knowledge regarding best practice because they have been exposed to the professional environment and dietetic support for a shorter period of time or it may reflect underlying stressors. Indeed, the transition from adolescence to adulthood and changes in lifestyle have all been associated with increased risk of EDs and body dissatisfaction (24,30). These results do suggest the importance of nutritional and mentoring support for young players in order for them to gain the knowledge and skills to obtain appropriate dietary intakes. Younger athletes place a greater emphasis on skinfolds; so, coaches and support staff may wish to talk about performance rather than body composition with new young players.
The cross-sectional nature of this study means that the long-term impact of these scores cannot be determined and causal inferences cannot be drawn. The inclusion of performance, injuries, and wellness measures throughout the season would have been beneficial. Furthermore, it is possible that the disordered eating responses seen by the younger athletes were due to a number of factors including their nutrition knowledge, exposure to a new environment and status within the squad, their living situations, and stress. A more detailed questionnaire including these factors would help elucidate these findings. However, the time required to complete a longer questionnaire in this inherently busy population would have significantly reduced participation.
It seems that some elite rugby union players do have some body image issues. It is, therefore, important that support staff are aware that some players, especially younger team members, may be experiencing these issues. These players may require additional support, when providing nutritional and body composition information such as improving nutrition knowledge and addressing stress levels.
Practical Applications
Body image is an issue for some rugby players, and coaches and support staff should consider this when discussing body composition. Younger athletes seem to be more “at risk” for disordered eating and may need additional nutritional support. Younger athletes place a greater emphasis on skinfolds. Coaches and support staff may wish to talk about performance rather than body composition with new young players.
Acknowledgments
The authors have no conflicts of interest to disclose.
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