This descriptive cross-sectional study assessed the perceptions, knowledge, and experiences of caffeine use by athletes competing at the 2005 Ironman Triathlon World Championships. Questionnaires were distributed to 140 athletes (105 men and 35 women, 40.3 ± 10.7 y old) representing 16 countries during prerace registration. A large proportion (73%) of these endurance athletes believe that caffeine is ergogenic to their endurance performance, and 84% believe it improves their concentration. The most commonly reported positive caffeine experiences related to in-competition use of cola drinks (65%) and caffeinated gels (24%). The athletes’ ability to accurately quantify the caffeine content of common food items was limited. The most popular sources of caffeine information were self-experimentation (16%), fellow athletes (15%), magazines (13%), and journal articles (12%). Over half the athletes (53%) could not identify an amount of caffeine required to improve their triathlon performance. Mean (± standard deviation) suggested doses were 3.8 (± 3) mg/kg body weight. Few side effects associated with taking caffeine during exercise were reported.
Search Results
Well-Trained Endurance Athletes’ Knowledge, Insight, and Experience of Caffeine Use
Ben Desbrow and Michael Leveritt
Exploring the Popularity, Experiences, and Beliefs Surrounding Gluten-Free Diets in Nonceliac Athletes
Dana M. Lis, Trent Stellingwerff, Cecilia M. Shing, Kiran D.K. Ahuja, and James W. Fell
Adherence to a gluten-free diet (GFD) for nonceliac athletes (NCA) has become increasingly popular despite a paucity of supportive medical or ergogenic evidence. This study aimed to quantify the demographics of NCA and determine associated experiences, perceptions, and sources of information related to GFD. Athletes (n = 910, female = 528, no gender selected = 5) completed a 17-question online survey. Forty-one percent of NCA respondents, including 18-world and/or Olympic medalists, follow a GFD 50–100% of the time (GFD > 50): only 13% for treatment of reported medical conditions with 57% self-diagnosing their gluten sensitivity. The GFD > 50 group characteristics included predominantly endurance sport athletes (70.0%) at the recreationally competitive level (32.3%), between 31 and 40 years of age (29.1%). Those who follow a GFD > 50 reported experiencing, abdominal/gastrointestinal (GI) symptoms alone (16.7%) or in conjunction with two (30.7%) or three (35.7%) additional symptoms (e.g., fatigue) believed to be triggered by gluten. Eighty-four percent of GFD > 50 indicated symptom improvement with gluten-removal. Symptom-based and non-symptom-based self-diagnosed gluten-sensitivity (56.7%) was the primary reason for adopting a GFD. Leading sources of GFD information were online (28.7%), trainer/coach (26.2%) and other athletes (17.4%). Although 5–10% of the general population is estimated to benefit clinically from a GFD a higher prevalence of GFD adherence was found in NCA (41.2%). Prescription of a GFD among many athletes does not result from evidence-based practice suggesting that adoption of a GFD in the majority of cases was not based on medical rationale and may be driven by perception that gluten removal provides health benefits and an ergogenic edge in NCA.
Effect of Ingested Fluid Composition on Exercise-Related Transient Abdominal Pain
Darren Peter Morton, Luis Fernando Aragón-Vargas, and Robin Callister
The present study investigated the effect of ingested fluid composition on the experience of exercise-related transient abdominal pain (ETAP). Forty subjects, susceptible to ETAP, completed 4 treadmill exercise trials: a no-fluid trial and flavored water (FW, no carbohydrate, osmolality = 48 mosmol/L, pH = 3.3), sports drink (SD, freshly mixed Gatorade®, 6% total carbohydrate, 295 mosmol/L, pH = 3.3), and reconstituted fruit juice (FJ, BERRI® orange, 10.4% total carbohydrate, 489 mosmol/L, pH = 3.2) trials. Measures of the experience of ETAP and gastrointestinal disturbances, particularly bloating, were quantified. The FJ was significantly (p < .01) more provocative of both ETAP and bloating than all other trials. There was no difference among the no-fluid, FW, and SD in the severity of ETAP experienced, although the difference between the no-fluid and SD approached significance at the .05 level (p = .056). There was a significant relationship between both the mean (r = 0.40, p < .01) and peak (r = 0.44, p < .01) levels of ETAP and bloating. When the level of bloating was controlled for, the FJ remained significantly (p < .01) more provocative of ETAP than the other conditions, with no difference between the FW and SD (p = .37). The results indicate that in order to avoid ETAP, susceptible individuals should refrain from consuming reconstituted fruit juices and beverages similarly high in carbohydrate content and osmolality, shortly before and during exercise. Further, the mechanism responsible for the heightened experience of ETAP in the FJ trial extends beyond a gastric mass explanation.
Athletes’ Opinions of Food Provision at the 2010 Delhi Commonwealth Games: The Influence of Culture and Sport
Sarah J. Burkhart and Fiona E. Pelly
The aim of this study was to investigate whether athletes’ opinion of food provision in the main dining hall of the athletes’ village at the Delhi 2010 Commonwealth Games varied according to cultural background, sport, stage of competition, and previous experience at similar events. A previously developed questionnaire was distributed over 3 meal periods to 351 athletes dining in the main dining hall during the course of the games (Sept. 23 to Oct. 4, 2010). Despite the challenges of food provision in a non-Western region, the availability of food and beverage items was rated highly. However, athletes from Western regions tended to rate food provision qualities lower than athletes from non-Western regions. Most athletes found it easy to find items to meet their nutrition needs; however, requests for sports foods, snacks, and culturally specific items were received. Power/sprint athletes were more critical of the food provision, whereas athletes from aesthetic sports tended to rate it more highly. Athletes farther from competition gave higher ratings for taste, while athletes who had more experience in this type of environment also tended to be more critical of the food provision. Overall daily mean opinion scores for taste and menu variety decreased over the games period. The results of this study can help organizers and caterers ensure that appropriate food and beverage are provided for athletes at major competition events.
Nutritional Intake during a Simulated Adventure Race
Ioná Zalcman Zimberg, Cibele Aparecida Crispim, Claudia Ridel Juzwiak, Hanna Karen Moreira Antunes, Ben Edwards, Jim Waterhouse, Sérgio Tufik, and Marco Túlio de Mello
The objective of the study was to describe the food intake of adventure racers during a competition simulated in the laboratory. Ten male athletes with international experience in adventure races took part in the study. The experiment lasted 67 hr (total distance covered 477.3 km), but 3 athletes did not finish the race. Food intake was recorded throughout the simulation. Athletes’ total energy expenditure was greater than their total energy intake (24,516 vs. 14,738 kcal), and the athletes obtained significantly more energy from food than from supplements. Carbohydrate intake was below the recommendation of 0.5–1.0 g · kg−1 · hr−1. These results indicate that guidelines for multiday adventure races are needed.
Endurance Training on Low-Carbohydrate and Grain-Based Diets: A Case Study
Richard R. Rosenkranz, Chad M. Cook, and Mark D. Haub
Purpose:
To illustrate the effects of low-carbohydrate (LC) and grain-based (GB) diets on body composition, biomarkers, athletic training, and performance in an elite triathlete.
Methods:
The athlete followed 2 dietary interventions for 14 d while maintaining a prescheduled training program. Pre- and post intervention measurements for each diet included plasma and serum samples, resting energy expenditure, body composition, and a performance bike ride.
Results:
Compared with the GB diet, the LC diet elicited more disruptions to training and unfavorable subjective experiences. Total cholesterol, HDL cholesterol, LDL cholesterol, ratings of perceived exertion, and heart rate were elevated on the LC diet. Blood insulin, resting lactate, post exercise lactate, and C-reactive protein were lowest on the LC diet.
Conclusion:
The LC diet resulted in both favorable and unfavorable outcomes. The primary observation was a disruption to scheduled training on the LC diet. Researchers should consider how the potential mediating effect of disruptions to training could influence pretest–posttest designs.
Reported Eating Behavior and Attitudes Improvement after a Nutrition Intervention Program in a Group of Young Female Dancers
Mary Yannakoulia, Marietta Sitara, and Antonia-Leda Matalas
The aim of the study was to evaluate the effectiveness of an intervention program that combined nutrition education and prevention of disordered eating in a group of female professional dance students. Thirty-two dancers, aged 19-25 years, took part in the program. Evaluation was done by a series of questionnaires that participants were asked to complete on 3 occasions. Assessments of body composition and dietary intake were also performed. Significant improvements in nutrition knowledge as well as a decrease in abnormal eating behavior and dietary restraint were observed at post intervention. At 6-month follow-up, the positive effects were maintained and further benefits were recorded; only nutrition knowledge showed a minor decline. Participants who were at higher risk for adopting abnormal eating behavior benefited the most from the program. These findings encourage the implementation of intervention programs in groups of young women that experience particular pressures for controlling body weight.
Heat Cramps during Tennis: A Case Report
Michael F. Bergeron
A 17-year-old, nationally ranked, male tennis player (AH) had been experiencing heat cramps during tennis match play. His medical history and previous physical exams were unremarkable, and his in-office blood chemistry profiles were normal. On-court evaluation and an analysis of a 3-day dietary record revealed that AH's sweat rate was extensive (2.5 L · hr−1) and that his potential daily on-court sweat sodium losses (89.8 mmol · hr of play') could readily exceed his average daily intake of sodium (87.0-174.0 mmol · day−1). The combined effects of excessive and repeated fluid and sodium losses likely predisposed AH to heat cramps during play. AH was ultimately able to eliminate heat cramps during competition and training by increasing his daily dietary intake of sodium.
Nutritional Aspects of Amenorrhea in the Female Athlete Triad
Joan E. Benson, Kathryn A. Engelbert-Fenton, and Patricia A. Eisenman
Female athletes experience a high incidence of menstrual abnormalities. This has critical health consequences because amenorrhea athletes are at greater risk of developing osteopenia and bone injury compared to normally menstruating athletes or nonathletic normally cycling females. Female performers and athletes are also at risk for developing disordered eating behaviors. There appears to be a connection between menstrual dysfunction, athletic training, and disordered eating, but how they relate is not fully understood. In this paper we explore how low calorie intakes, nutritional inadequacies, vegetarianism, low body fat stores, and specific training behaviors may contribute to the abnormal menstrual patterns seen in this population. Recommendations for the detection and prevention of eating and training problems and consequent menstrual abnormalities are included.
Nutrient Intake of an Ultraendurance Cyclist
Alice K. Lindeman
Meeting the energy demands of ultraendurance cycling requires careful planning and monitoring of food and fluid intake. This case study presents the nutrient intake of a cyclist while training for and competing in the Race Across AMerica (RAAM). Carbohydrate accounted for 65% of the calories consumed during training (4,743 kcal), 75% during 24-hr races (10,343 kcal), and 78% during RAAM (8,429 kcal). Gastrointestinal complaints during RAAM included nausea, feeling of fullness, and abdominal distension. Although probably exacerbated by sleep deprivation, these problems were all diet related. Based on this experience, it appears that by controlling the carbohydrate concentration of beverages, limiting dietary fiber, and relying on carbohydrate as the primary energy source, one could both control gastrointestinal symptoms and promote optimal performance in training and in ultramarathon cycling.