Volume 88, Issue 5 , Pages 681-682, May 2007
Prevalence of Female Athlete Triad Characteristics in a Club Triathlon Team
Article Outline
Abstract
Hoch AZ, Stavrakos JE, Schimke JE. Prevalence of female athlete triad characteristics in a club triathlon team.
Objective
To determine the prevalence of the female athlete triad in club triathletes.
Design
Cross-sectional.
Setting
Academic medical center in the midwestern United States.
Participants
Fifteen women (mean age, 35±6y).
Interventions
Not applicable.
Main Outcome Measures
Disordered eating and menstrual status were determined by questionnaires. Energy status was determined by a 3-day food record, resting energy expenditure, and exercise energy output. Bone mineral density (BMD) was measured in the total left hip and lumbar spine (L2-4) by dual-energy x-ray absorptiometry.
Results
Sixty percent of the triathletes were found to be in calorie deficit, 53% had a carbohydrate deficit, 47% had a fat deficit, 40% had a protein deficit, and 33% had a calcium deficit. Forty percent of triathletes reported a history of amenorrhea. BMD was normal in the lumbar spine (L2-4) (1.3±0.1g/cm2) and total left hip (1.1±0.1g/cm2).
Conclusions
Triathletes are at risk for components of the female athlete triad. Continued efforts need to be directed at prevention through education of athletes, coaches, parents, and health care professionals.
Key Words: Amenorrhea, Athletics, Eating disorders, Female, Rehabilitation
IN A WORLD INCREASINGLY devoted to participation in professional and recreational athletic events, the triathlon has gained significant attention within the past 2 decades. A triathlon is defined as consecutive swimming, biking, and running events of varying distances. The diversity of training and the development of a balanced degree of fitness have contributed to the success of this athletic endeavor.
The female athlete triad (triad) is an interrelated condition of disordered eating, amenorrhea, and osteoporosis. It appears to be more common in endurance and aesthetic sports.
The purpose of this study was to determine the prevalence of triad characteristics in a recreational women’s triathlon team.
Methods
Fifteen women from the same triathlon team volunteered to participate in this study and signed an informed consent in accordance with our institutional review board. All of the triathletes competed at a recreational level except for 2 who were professionals. Subjects trained on an average of 5 days per week for at least 90 minutes. Subjects reported starting athletics at a mean age of 12.6 years. None had a history of anorexia or bulimia. Subjects completed menstrual and health questionnaires, which were reviewed by the primary investigator (AZH). Eating habits and attitudes were assessed by the Eating Attitude Test (EAT-26), which has been validated for anorexia.1 Each subject completed a body image questionnaire.
We calculated energy status on each subject from a prospective 3-day food diary2 using a Nutrient Analysis program.a Resting energy expenditure (REE) was calculated by the Harris-Benedict equation and multiplied by an activity factor of 1.1, which was used to estimate energy expended from daily activities of living.3 Energy burned through exercise was estimated using known calculations for time of exercise for running, swimming, and biking. These calculations were based on factors associated with the participants’ weight, age, sex, and intensity of exercise.4 The total calories expended from exercise was then added to the adjusted energy expenditure (REE × 1.1). This value of total energy expended was compared with the subjects’ caloric intake to determine if an energy deficit was present. The sports dietitian was able to calculate the participants’ daily carbohydrate, protein, and fat requirements and compare these values with the amount of macronutrients consumed. Diet records were recorded during the training season and consisted of 2 weekdays and 1 weekend day. Finally, calcium intake was recorded based on the 3-day food diary and compared with daily requirements for age.5
We measured bone mineral density (BMD) (in g/cm2) of the lumbar spine (L2-4) and total left hip by dual energy x-ray absorptiometry (DXA)b to assess for evidence of reduced BMD for age.
Results
Mean age ± standard deviation (SD) of the subjects was 35±6 years. Nutritional analysis revealed that 60% of the triathletes were in a calorie deficit. Fifty-three percent had a carbohydrate deficit, 47% had a fat deficit, 40% had a protein deficit, and 33% had a calcium deficit. The average calcium deficit was −307±283mg, average calorie deficit of the affected group was −245±187kcal, and the average fat deficit was −15±11g. Average carbohydrate and protein deficits were −70±30g and −15±7g, respectively. Calorie deficit is defined as calorie intake not commensurate with the athlete’s caloric expenditure. Calcium deficit was defined as an average daily intake of less than 1300mg/d.5 The average score on the EAT-26 was 4.3±4.4 (>15 is abnormal).1 This self-reported questionnaire consists of 26 questions and is scored on a 0-to-6 Likert scale. A score of greater than 30 on the EAT-26 represents a high likelihood of anorexia and a score between 15 and 30 represents a subclinical group with disordered eating habits and anorectic attitudes. The body image silhouette was 3.2±0.2. Subjects were asked to circle the body type they considered to be the “ideal” triathlete from a validated 9-body silhouette scale,6 which ranges from an extremely thin or nearly anorexic figure at position 1 to a very overweight figure at position 9. A calorie deficit (>200kcal) was considered consistent with disordered eating for the purposes of this study.
Forty percent of the participants admitted to a history of primary or secondary amenorrhea. Average length of amenorrhea was 14±2 months. None were currently amenorrheic.
DXA revealed a mean BMD ± SD of 1.3±0.1g/cm2 in the lumbar spine (L2-4), which corresponds to a T score of 0.7 and z score of 0.8. The average BMD of the total hip was 1.1±0.1g/cm2, which corresponds to a T score of 0.7 and z score of 0.8. Both T score and z score values correspond to values that are within normative limits based on the World Health Organization (WHO)7 classification system and criteria published by the International Society for Clinical Densitometry (ISCD).8 In 1994, WHO established criteria for making the diagnosis of osteoporosis, as well as determining levels that predict higher chances of fractures for postmenopausal white women. These criteria are based on comparing BMD in a particular patient to the average 20-year-old woman. BMD values, referred to as T score, that fall well below the average for the 20-year-old (stated statistically as 2.5 SDs below the average) are diagnosed as “osteoporotic.” If a patient has a BMD T-score value between −1.0 and −2.5 SDs below average, they are considered to be “osteopenic.” The z score is the number of SDs below average for a person of the same age, sex, and race. ISCD recommends using z scores for premenopausal adolescents and children. If a z score is less than −2.0 using a pediatric database of age-matched controls, then ISCD recommends using the term “low bone mineral density for age.”8 Subjects with a history of amenorrhea had the lowest BMD. This was not statically significant given the small sample size, however.
Overall, 60% of the subjects had at least 1 component of the triad, with 27% of these having 2 components of the triad (disordered eating and history of amenorrhea). Finally, 53% of the subjects were not able to identify all 3 components of the triad and 60% were not aware of daily calcium requirements for age.
Discussion
This was a well-educated group of athletes that showed relatively normal body image. They showed several triad characteristics, however. Of the 3 components of the triad, disordered eating, specifically caloric restriction, was the most prevalent followed by a history of amenorrhea. None of the subjects had an abnormal BMD value. Over half of the team showed 1 or more triad characteristics.
The term disordered eating encompasses a spectrum of abnormal behaviors that may range from a mild preoccupation with food and exercise to a diagnosis of anorexia or bulimia according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.9 These disorders often stem from internal or external pressures to be thin, or they may be the result of the misconception that thinness improves athletic performance. It is estimated that anywhere from 15% to 65% of female athletes suffer from some form of disordered eating pattern.10 In this study, 60% of the participants were found to be in a calorie deficit.
Athletic associated amenorrhea is a diagnosis of exclusion. It was formerly believed that the stress of exercise and low body fat were the causes of exercise associated amenorrhea. Recent studies by Loucks11 have found that diminished energy intake, rather than exercise, stress, or body fat depletion, was the regulating factor in the cessation of menses in active women.
BMD values in premenopausal women can be calculated by T score according to WHO.7 A T score of −1.0 or less is classified as osteopenia and −2.5 or less is considered osteoporosis. It should be noted that these labels may not be entirely applicable to this subject population, because the WHO osteoporosis criteria were designed for postmenopausal women in whom the mechanism of low BMD is the result of premature bone loss, and the T score was designed to predict fracture risk. ISCD8 recommends using the term “low BMD” in premenopausal women who do not have risk factors and have a z score less than 2.0. ISCD reserves the term osteoporosis for premenopausal women with secondary risk factors. Fortunately, none of the athletes in this study showed evidence of abnormal BMD in the hip or lumbar spine. In addition, BMD was obtained at 1 point in time in this study. Therefore, we were unable to determine who had a loss, gain, or no change over time.
Conclusions
Women triathletes are at risk for components of the female athlete triad, especially disordered eating. The participants in this study were college-educated women living in a major metropolitan area with normal body image, yet over half of these athletes were unaware of the triad and its potential dangers. This underscores the need for continued effort directed at prevention of the triad through education of athletes, coaches, parents, and other health professionals and for comprehensive clinical programs to treat the triad.
Suppliers
References
- . The eating attitudes test: psychometric features and clinical correlates. Psychol Med. 1982;12:871–878
- Use of biological markers to validate self-reported dietary intake in a random sample of the European Prospective Investigation into Cancer United Kingdom Norfolk cohort. Am J Clin Nutr. 2001;74:188–196
- . A biometric study of basal metabolism in man. Washington (DC): Carnegie Institute of Washington; 1919;Publication No. 279.
- . Energy. In: Mahan KL, Escott-Stump S editor. Krause’s food, nutrition and diet therapy. 10th ed.. Philadelphia: WB Saunders; 2000;p. 19–30
- Osteoporosis prevention, diagnosis, and therapy (NIH Consens Statement). 2000;17:1–45
- . Does obesity run in families because of genes? (An adoption study using silhouettes as a measure of obesity). Acta Psychiatr Scand Suppl. 1993;370:67–72
- . Assessment of fracture risk and its application to screening for postmenopausal osteoporosis. Geneva: WHO; 1994;Technical Report Series 843.
- . Diagnosis of osteoporosis in men, premenopausal women, and children. J Clin Densitom. 2004;7:17–26
- . Eating disorders. In: First MB editors. Diagnostic & statistical manual of mental disorders: DSM-IV. Washington (DC): APA; 1994;p. 539–550
- . American College of Sports Medicine position stand (The Female Athlete Triad). Med Sci Sports Exerc. 1997;29:1669–1671
- . Energy availability, not body fatness, regulates reproductive function in women. Exerc Sport Sci Rev. 2003;31:144–148
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated.
PII: S0003-9993(07)00172-4
doi:10.1016/j.apmr.2007.02.035
© 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Volume 88, Issue 5 , Pages 681-682, May 2007
