Department of Exercise and Sport Science
Narrative: Body composition, bone mineral density, and energy balance in collegiate female athletes throughout a competitive training season
Department of Exercise and Sport Science
Statement of the Problem/Significance of the Project
Physiological, functional, and biomechanical demands of a sport are often reflected in an athlete’s physical characteristics (Malina, 1995; Shepard, 1998; Maetsu et al., 2000). In fact, it is often the case that the demands of the sport dictate the morphology, or the structure and form of the human body. In addition, the nature and level of the performance are also likely influences to the physical characteristics associated with training for a sport (Carter, 1984). Examples of these characteristics include body composition and bone mineral density.
The uniqueness of the female athlete demands an even further understanding of the relationship between training and its impact on physical characteristics. When working with the female athlete, special issues to be considered include: menstruation and menstrual dysfunction, pregnancy, osteoporosis, and eating disorders (Wilmore & Costill, 2004). The combination of disordered eating, menstrual cycle dysfunction (amenorrhea), and bone mineral disorders (osteoporosis) has been termed the Female Athlete Triad (ACSM, 1997). In addition to the female athlete, according to the ACSM Position Stand (1997), potentially all physically active girls and women are at risk of developing one or more of the components of the female athlete triad.
The components of the female athlete triad are interrelated in their etiology, pathogenesis, and consequences, not only in terms of health but also, in terms of performance (ACSM, 1997). If physical characteristics are influenced by the training demands of the sport, it becomes essential to understand the changes that occur to those characteristics. In particular, those sports that emphasize low body weight (swimmers, gymnasts, cross country runners, etc) may present an additional risk for promoting the development of one or more components of the triad. The concern with the female athlete triad is not only in its impact on performance but its risk of morbidity (illness or disease) and mortality (death) (ACSM, 1997). With this in mind, it is critical to understand the prevalence of not only the female athlete triad as a whole, but each component of the triad.
According to the ACSM Position Stand (1997), there is a need for prevalence studies to identify those who have or are at risk for the female athlete triad. This includes having one or more of the components of the triad. Recently, prevalence studies using elite level Norwegian athletes reported approximately 4.3% of the athletes met the criteria for all components of the triad (Torstveit & Sundgot-Borgen, 2005b). In addition, Torstveit and Sundgot-Borgen (2005a) found approximately 60.4% of elite level athletes and 69.2% of controls from the Norwegian population were at risk for the female athlete triad. Furthermore, when comparisons were made within age groups, those in the age range of 20-29 years were at an increased risk. However, it has been suggested females with one component should be screened for the other components (ACSM, 1997). While Torstveit and Sundgot-Borgen (2005a, 2005b) discussed the prevalence in elite level athletes and non-athletes, to date there have been no controlled prevalence studies on non-elite level athletes. If the nature and level of performance influence characteristics relevant to the triad, information concerning collegiate level athletes, such as those in a Division III program, may provide additional insight into the triad.
Body composition, menstrual cycle dysfunction (i.e., amenorrhea), and osteoporosis are interrelated. Body composition provides an estimate of the body weight that is fat mass and fat-free mass, a two compartment model. Dual energy X-ray absorptiometry (DEXA), defines the body as a three compartment model (fat mass, fat free mass, bone mineral content), and uses that model in estimating body composition. Factors related to disordered eating and caloric restriction (i.e. energy balance) will affect body composition and bone mineral density. In turn, disordered eating and caloric restriction may affect the menstrual cycle. Amenorrhea, or more importantly, secondary amenorrhea, defined as the absence of three or more consecutive menstrual cycles after the attainment of menarche, has been shown to be related to energy imbalance (Loucks, Verdun, & Heath, 1998). In addition, excessive exercise, enough to induce amenorrhea, is associated with a decrease in bone mineral density, which can lead to more serious problems such as an increased risk of fractures (ACSM, 1997; Miller, 2003). As a result, these factors combined or alone may not only affect performance but also may lead to other problems during or after an athletic career.
Due to the inter-relatedness of the components of the triad, information concerning the cause of the triad is limited. However, a key issue related to the development of the triad is a negative energy balance (Manore, 2002). This imbalance may stem from caloric restriction or disordered eating, which are prevalent in leanness sports, or those, which place an emphasis on body composition. Additionally, caloric restriction may alter the musculoskeletal and endocrine systems (ACSM, 1997). In other words, not only will alterations to caloric intake impact the menstrual cycle but may also influence body composition (fat mass and fat-free mass) and bone mineral density. Therefore, to completely understand the components of the female athlete triad it is important to look at body composition, bone mineral density, menstrual cycle irregularities, and nutritional variables.
The ACSM Position Stand (1997) suggests that physically active girls and women should be educated about proper nutrition, safe training practices, and warning signs and symptoms of the triad. It is also suggested that athletes and coaches be educated about the possible health consequences of inadequate energy intake and potentially excessive exercise habits leading to a negative energy balance (Torstveit & Sundgot-Borgen, 2005b). This project details the nutritional variables that are critically related to the components of the triad. Furthermore, this project is an attempt to better understand the female athlete triad in female collegiate Division III athletes in at risk and not at risk sports. In addition, it is my intention to gain an understanding of the longitudinal effects of participation in a collegiate sport on variables associated with the female athlete triad. Therefore, the purpose of this project is to evaluate body composition, bone mineral density, and energy balance during a training season (1 year) and across a collegiate athletic career (4 years).
Completion of this project will provide a further insight into the prevalence of the female athlete triad in at risk and not at risk female competitive athletes. In addition, a further awareness of the changes that occur with participation in competitive athletics from one year to the next will assist in the understanding of the development of the competitive athlete. This in turn may assist both athletes and coaches in planning effective training programs and its influence on performance.
Specific objectives include the following:
1. Prevalence, using the criteria from Torstviet & Sundgot-Borgen (2005b), of the female athlete triad in Division III collegiate athletes in high sports and non-high risk sports.
2. Prevalence, using the criteria from Torstviet & Sundgot-Borgen (2005b), of any of the three components of the female athlete triad in Division III collegiate athletes in high risk sports and non-high risk sports.
3. Changes in body composition (fat mass and fat-free mass) and bone mineral density within a competitive collegiate season (pre-season, post-season).
4. Cross-sectional analysis of changes in body composition (fat mass and fat-free mass) and bone mineral density across years of participation in Division III collegiate female athletes.
5. Caloric intake during a competitive season (preseason, post-season).
Subjects solicited for this project will include approximately 90 University of Wisconsin – La Crosse female collegiate athletes (aged 17-23 years). Specific sports targeted will include those listed as at risk (swimmers, gymnasts) and as not at risk (volleyball) for the female athlete triad as recognized by the ACSM Position Stand (1997). The anticipated start date of this project is August 2006. The month of August 2006 will be used to prepare for the project which includes discussion with coaches in terms of potential testing dates that correspond to the desired phases of the training season. In addition, the Principle Investigator will use this time to train the Graduate Student Investigator on the nutritional interviews that will take place for each testing session. And finally, UW-L IRB will be applied for during this month. The projected end time of this project is April/ May 2007. The intention of this project is to begin a longitudinal analysis of these athletes as they progress in their collegiate athletic career. The longitudinal assessment first involved swimmers and gymnasts as they were observed in a previous project (2005-2006) and will continue until the freshman entering in 2005-06 graduate in 2008-09. IRB renewal will be sought upon each new school year.
Recruitment of subjects will begin at the first meeting of the athletes with their respective coach. During the initial or pre-season practices all subjects will be asked to perform their first series of testing. Upon agreement with the respective sports coaches, the competition or post-season testing sessions will be determined. Athletes will then be informed of the dates. In addition, athletes will be asked to fill out a questionnaire regarding their physical activity during the month of August. Questions will include approximate frequency, volume, and intensity of the sessions. This information is critical to interpreting the measures to be taken during the pre-season.
During the school year, athletes will visit the Human Performance Laboratory on two separate dates. Visits will correspond to pre-season (September/October) and post-season (March/April). During each of the testing periods, athletes will complete a body composition and bone mineral density assessment, menstrual cycle questionnaire, and a 24 hour dietary recall.
At each visit, athletes will undergo body composition and bone density assessment using Dual Energy X-Ray Absorptiometry (DEXA). This process requires athletes to be lying still for approximately 10 minutes. The DEXA scan will provide information concerning percent body fat, distribution of fat mass and fat-free mass throughout the body, total bone mineral density, and site specific bone mineral density (spine and hip). The Principle Investigator has been trained in using the DEXA and therefore will administer the body composition and bone density analysis. Procedures will be explained to each participant prior to performing the DEXA.
To further understand the bone mineral density of the athletes, skeletal breadths will be taken to estimate the robustness or width of the skeleton. Skeletal breadths are taken using an anthropometer using certain bony landmarks and include biacromial (shoulders), bicristal (hips), biepicondylar (elbows), and bicondylar (knees). Skeletal breadths will only be taken during the first testing session.
Upon completion of the DEXA and body measures, athletes will be asked to fill out questionnaires regarding menstrual cycle history. Questionnaires include information concerning regularity/irregularity of the menstrual cycle and use of birth control hormones. The questionnaires regarding menstrual status will be given because of the interaction of menstrual cycle dysfunction on body composition and bone density. These questionnaires will also assist in determining if any athlete has any form of menstrual dysfunction (i.e., primary or secondary amenorrhea, oligomenorrhea).
In the same week as the body composition analysis, athletes will be asked to perform a 24 hour dietary record and recall. This requires the athletes to record their food and beverage intake for a 24-hour period using an Eating Behavior Journal. Additional information in the journal includes time of day of food/drink intake, degree of hunger, social setting, and any other comments deemed important to the athlete to record. The morning after the recall, subjects will report to the Physiology Laboratory in the Health Science Center for an interview with the Graduate Student Investigator. The interview will assist the athlete in remembering the food and beverage intake from the day prior. Food models and prompt questions will be used to provide more reliable results from the athlete’s Eating Behavior Journal. These interviews will last approximately 30 minutes per athlete. The graduate student in charge of interviewing will spend the month of August 2006, practicing their interviewing techniques and learning the computer software used in the analysis. Information from the nutritional analysis will include total calories consumed as well as total carbohydrates, fats, proteins, vitamins, minerals, and amino acids, all of which may have a potential impact on bone density. Upon the final visit, after the interview, the subject will fill out the SCOFF questionnaire. This is an assessment tool used to screen for eating disorders. If the SCOFF questionnaire indicates an eating disorder is present, the Investigator will refer the subject to the Health Science Center for counseling.
To completely understand the interaction of the components of the triad to the athlete’s performance, information regarding training amounts will also be obtained from the respective coach, instead of from the athlete. Training information from the coach will include general information of the group as a whole in terms of training volumes (amount/week) during the season. At the end of the season, performance measures specific to each sport will also be collected (e.g., performance score, final ranking, performance time, time spent playing, kills/aces/digs).
Data will be primarily analyzed in terms of differences that occur within a training season. In addition, since the longitudinal aspect of this study will take two more years, a cross-sectional analysis will be performed. This information will provide us with an initial, though limited, understanding of the changes that occur with training across a collegiate athletic career. Criteria used to classify an athlete with the female athlete triad will be the same as that described by Torstveit & Sundgot-Borgen (2005b) which included two categories, a “moderate-severe” group or Triad Stage 1 and a “severe” group or Triad Stage 2. Classifications include diagnosis with an eating disorder using the SCOFF questionnaire, a low bone mineral density in comparison to standards provided by the DEXA manufacturer, and menstrual dysfunction as defined by having primary amenorrhea, secondary amenorrhea, or oligomenorrhea (irregular menstrual cycles).
Final Product and Dissemination
There are many benefits to participation in this longitudinal project. One direct benefit includes allowing the athlete to learn information concerning her body composition, bone mineral density, and caloric intake throughout a season. In addition, this project, with its longitudinal design, may aid in a further understanding of components of the female athlete triad that may be present in athletes in at risk sports and not at risk sports. Coaches, athletes, and sports medicine communities will also benefit from the knowledge gained in this project. It is my intention of this project to develop guidelines that may assist the athlete in preparation for participation in competitive collegiate sports as well as understanding proper training and nutrition.
It is anticipated a publishable manuscript will be a result of this project. Few studies have involved Division III collegiate athletes and reported specific information concerning all three components of the triad and their relationship to performance. In addition, it is anticipated this project will lead to more discussion over the prevalence and an understanding of the female athlete triad. A further result of this study will be the attempt to understand changes that occur longitudinally in a group of competitive female athletes.
American College of Sports Medicine Position Stand. (1997). The female athlete triad. Medicine and Science in Sports and Exercise, 29(5), i-ix.
Carter, J.E.L. (1985). Morphological factors limiting human performance. In Limits of Human Performance (edited by D.H. Clarke and H.M. Eckert), 106-117. Champaign, IL: Human Kinetics.
Loucks, A.B., Verdun, M., & Heath, E.M. (1998). Low energy availability, not stress of exercise, alters LH pulsatility in exercising women. Journal of Applied Physiology, 84, 37-46.
Maetsu, J., Jurimae, J., and Jurimae, T. (2000). Relationships between anthropometric variables and different rowing ergometer tests in heavy weight and light weight male rowers. Papers on Anthropology, 125-132.
Manore, M.M. (2002). Dietary recommendations and athletic menstrual dysfunction. Sports Medicine, 32, 887-901.
Malina, R.M. (1995). Anthropometry. In Physiological Assessment of Human Fitness (edited by P.J. Maud and C. Foster), pp. 205-219. Champaign, IL: Human Kinetics.
Miller, K.K. (2003). Mechanisms by which nutritional disorders cause reduced bone mass in adults. Journal of Women’s Health, 12(2), 145-150.
Torstveit, M.K. & Sundgot-Borgen, J. (2005a). The female athlete triad: Are elite athletes at increased risk? Medicine and Science in Sports and Exercise, 37(2), 184-193.
Torstveit, M.K. & Sundgot-Borgen, J. (2005b). The female athlete triad exists in both elite athletes and controls. Medicine and Science in Sports and Exercise, 37(9), 1449-1459.
Wilmore, J.H. & Costill, D.L. (2004). Physiology of sport and exercise. Champaign, IL: Human Kinetics.
SUMMARY PROJECT BUDGET
Project Title Body composition, bone mineral density, and energy balance in collegiate female athletes throughout a competitive training season
Project Director(s) Rebecca A. Battista, Ph.D.
I. Salaries and Wages
A. Faculty Stipend(s)
1. Name Rebecca A. Battista, Ph.D. $ 6094.80
2. Name $
B. Student Help $ 5850.00
Graduate Student Investigator for training, and pre and postseason nutritional interviews.
Salaries & Wages Subtotal $ 11,944.80
II. Travel $ 0
A. Meals $
B. Transportation $
C. Lodging $
Travel Subtotal $ 0
III. Supplies & Services
A. Consumable Supplies $ 0
B. Duplicating, postage, communications, etc. $ 45.00
Duplicating journals, questionnaires, Zip disk for DEXA
Supplies & Services Subtotal $ 45.00
IV. Equipment $ 0
Equipment Subtotal $
TOTAL REQUESTED $ 11,989.80