Jenna C. Gibbs
University of Waterloo
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British Journal of Sports Medicine | 2014
Mary Jane De Souza; Aurelia Nattiv; Elizabeth A. Joy; Madhusmita Misra; Nancy I. Williams; Rebecca J. Mallinson; Jenna C. Gibbs; Marion P. Olmsted; Marci Goolsby; Gordon O. Matheson
The Female Athlete Triad is a medical condition often observed in physically active girls and women, and involves three components: (1) low energy availability with or without disordered eating, (2) menstrual dysfunction and (3) low bone mineral density. Female athletes often present with one or more of the three Triad components, and an early intervention is essential to prevent its progression to serious endpoints that include clinical eating disorders, amenorrhoea and osteoporosis. This consensus statement represents a set of recommendations developed following the 1st (San Francisco, California, USA) and 2nd (Indianapolis, Indiana, USA) International Symposia on the Female Athlete Triad. It is intended to provide clinical guidelines for physicians, athletic trainers and other healthcare providers for the screening, diagnosis and treatment of the Female Athlete Triad and to provide clear recommendations for return to play. The 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad expert panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision-making regarding sport participation, clearance and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team and implementation of treatment contracts. This consensus paper has been endorsed by the Female Athlete Triad Coalition, an International Consortium of leading Triad researchers, physicians and other healthcare professionals, the American College of Sports Medicine and the American Medical Society for Sports Medicine.
Current Sports Medicine Reports | 2014
Elizabeth A. Joy; Mary Jane De Souza; Aurelia Nattiv; Madhusmita Misra; Nancy I. Williams; Rebecca J. Mallinson; Jenna C. Gibbs; Marion P. Olmsted; Marci Goolsby; Gordon O. Matheson; Michelle T. Barrack; Louise M. Burke; Barbara Drinkwater; Connie Lebrun; Anne B. Loucks; Margo Mountjoy; Jeanne F. Nichols; Jorunn Sundgot Borgen
The female athlete triad is a medical condition often observed in physically active girls and women and involves three components: 1) low energy availability with or without disordered eating, 2) menstrual dysfunction, and 3) low bone mineral density. Female athletes often present with one or more of the three triad components, and early intervention is essential to prevent its progression to serious end points that include clinical eating disorders, amenorrhea, and osteoporosis. This consensus statement presents a set of recommendations developed following the first (San Francisco, CA) and second (Indianapolis, IN) International Symposia on the Female Athlete Triad. This consensus statement was intended to provide clinical guidelines for physicians, athletic trainers, and other health care providers for the screening, diagnosis, and treatment of the female athlete triad and to provide clear recommendations for return to play. The expert panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision making regarding sport participation, clearance, and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team, and implementation of treatment contracts.
American Journal of Sports Medicine | 2014
Michelle T. Barrack; Jenna C. Gibbs; Mary Jane De Souza; Nancy I. Williams; Jeanne F. Nichols; Mitchell J. Rauh; Aurelia Nattiv
Background: Identifying the risk factors associated with a bone stress injury (BSI), including stress reactions and stress fractures, may aid in targeting those at increased risk and in formulating prevention guidelines for exercising girls and women. Purpose: To evaluate the effect of single or combined risk factors as defined by the female athlete triad—a syndrome involving 3 interrelated spectrums consisting of energy availability, menstrual function, and bone mass—with the incidence of BSIs in a multicenter prospective sample of 4 cohorts of physically active girls and women. Study Design: Cohort study; Level of evidence, 3. Methods: At baseline, participants’ (N = 259; mean age, 18.1 ± 0.3 years) anthropometric characteristics, eating attitudes and behaviors, menstrual function, sports participation or exercise activity, and pathological weight control behaviors were assessed. Dual-energy x-ray absorptiometry (DXA) measured the bone mass of the whole body, total hip, femoral neck, lumbar spine, and body composition. Participants were followed prospectively for the occurrence of injuries; those injuries confirmed by a physician were recorded. Results: Twenty-eight participants (10.8%) incurred a BSI. Forty-six percent of those who had ≥12 h/wk of purposeful exercise, a bone mineral density (BMD) Z score <–1.0, and who exhibited 3 to 4 of the following: BMI <21.0 kg/m2, oligo- or amenorrhea, elevated dietary restraint, and/or participation in a leanness sport exercise/activity at baseline, incurred a BSI during the prospective study period. Single factors significantly (P < .05) associated with the development of a BSI included ≥12 h/wk of purposeful exercise (14.7%), BMI <21.0 kg/m2 (15.3%), and low bone mass (BMD Z score <–1.0; 21.0%). The strongest 2- and 3-variable combined risk factors were low BMD (Z score <–1.0) + ≥12 h/wk of exercise, with 29.7% incurring a BSI (odds ratio [OR], 5.1; 95% CI, 2.2-12.1), and ≥12 h/wk of exercise + leanness sport/activity + dietary restraint, with 46.2% incurring a BSI (OR, 8.7; 95% CI, 2.7-28.3). Conclusion: In the sample, which included female adolescents and young adults participating in competitive or recreational exercise activities, the risk of BSIs increased from approximately 15% to 20% for significant single risk factors to 30% to 50% for significant combined female athlete triad–related risk factor variables. These data support the notion that the cumulative risk for BSIs increases as the number of Triad-related risk factors accumulates.
Medicine and Science in Sports and Exercise | 2013
Jenna C. Gibbs; Nancy I. Williams; Mary Jane De Souza
PURPOSE The female athlete triad (Triad) is a syndrome linking low energy availability (EA) with or without disordered eating (DE), menstrual disturbances (MD), and low bone mineral density (BMD) in exercising women. The prevalence of Triad conditions (both clinical and subclinical) has not been clearly established.The purpose of this review is to evaluate the studies that determined the prevalence of clinical or subclinical Triad conditions (low EA, DE, MD, and low BMD) in exercising women and in women participating in lean (LS) versus nonlean sports (NLS) using self-report and/or objective measures. METHODS A review of publications using MEDLINE and PubMed was completed. Randomized controlled trials and observational studies that evaluated the prevalence of clinical and subclinical Triad conditions (MD, low BMD, low EA, and DE) in exercising women were included. RESULTS Sixty-five studies were identified for inclusion in this review (n = 10,498, age = 21.8 ± 3.5 yr, body mass index = 20.8 ± 2.6 kg·m; mean ± SD). A relatively small percentage of athletes (0%-15.9%) exhibited all three Triad conditions (nine studies, n = 991). The prevalence of any two or any one of the Triad conditions in these studies ranged from 2.7% to 27.0% and from 16.0% to 60.0%, respectively. The prevalence of all three Triad conditions in LS athletes versus NLS athletes ranged from 1.5% to 6.7% and from 0% to 2.0%, respectively. LS athletes demonstrated higher prevalence rates of MD and low BMD (3.3% vs 1.0%), MD and DE (6.8%-57.8% vs 5.4%-13.5%), and low BMD and DE (5.6% vs 1.0%) than the NLS athletes. CONCLUSIONS Although the prevalence of individual/combined Triad conditions is concerning, our review demonstrates that additional research on the prevalence of the Triad using objective and/or self-report/field measures is necessary to more accurately describe the extent of the problem.
Clinical Journal of Sport Medicine | 2014
Mary Jane De Souza; Aurelia Nattiv; Elizabeth A. Joy; Madhusmita Misra; Nancy I. Williams; Rebecca J. Mallinson; Jenna C. Gibbs; Marion P. Olmsted; Marci Goolsby; Gordon O. Matheson
Abstract:The Female Athlete Triad is a medical condition often observed in physically active girls and women, and involves 3 components: (1) low energy availability with or without disordered eating, (2) menstrual dysfunction, and (3) low bone mineral density. Female athletes often present with 1 or more of the 3 Triad components, and an early intervention is essential to prevent its progression to serious endpoints that include clinical eating disorders, amenorrhea, and osteoporosis. This consensus statement represents a set of recommendations developed following the first (San Francisco, California) and second (Indianapolis, Indianna) International Symposia on the Female Athlete Triad. It is intended to provide clinical guidelines for physicians, athletic trainers, and other health care providers for the screening, diagnosis, and treatment of the Female Athlete Triad and to provide clear recommendations for return to play. The 2014 Female Athlete Triad Coalition Consensus Statement on Treatment and Return to Play of the Female Athlete Triad Expert Panel has proposed a risk stratification point system that takes into account magnitude of risk to assist the physician in decision-making regarding sport participation, clearance, and return to play. Guidelines are offered for clearance categories, management by a multidisciplinary team, and implementation of treatment contracts. This consensus paper has been endorsed by The Female Athlete Triad Coalition, an International Consortium of leading Triad researchers, physicians, and other health care professionals, the American College of Sports Medicine, the American Medical Society for Sports Medicine, and the American Bone Health Alliance.
Bone | 2011
Jennifer L. Scheid; Rebecca J. Toombs; Gaele Ducher; Jenna C. Gibbs; Nancy I. Williams; M.J. De Souza
BACKGROUND In women with anorexia nervosa, elevated fasting peptide YY (PYY) is associated with decreased bone mineral density (BMD). Prior research from our lab has demonstrated that fasting total PYY concentrations are elevated in exercising women with amenorrhea compared to ovulatory exercising women. PURPOSE The purpose of this study was to assess the association between fasting total PYY, average monthly estrogen exposure and BMD in non-obese premenopausal exercising women. METHODS Daily urine samples were collected and assessed for metabolites of estrone 1-glucuronide (E1G) and pregnandiol glucuronide (PdG) for at least one menstrual cycle if ovulatory or a 28-day monitoring period if amenorrheic. Fasting serum samples were pooled over the measurement period and analyzed for total PYY and leptin. BMD and body composition were assessed by dual-energy X-ray absorptiometry. Multiple regression analyses were performed to determine whether measures of body composition, estrogen status, exercise minutes, leptin and PYY explained a significant amount of the variance in BMD at multiple sites. RESULTS Premenopausal exercising women aged 23.8±0.9years with a mean BMI of 21.2±0.4kg/m(2) exercised 346±48min/week and had a peak oxygen uptake of 49.1±1.8mL/kg/min. Thirty-nine percent (17/44) of the women had amenorrhea. Fasting total PYY concentrations were negatively associated with total body BMD (p=0.033) and total hip BMD (p=0.043). Mean E1G concentrations were positively associated with total body BMD (p=0.033) and lumbar spine (L2-L4) BMD (p=0.047). The proportion of variance in lumbar spine (L2-L4) BMD explained by body weight and E1G cycle mean was 16.4% (R(2)=0.204, p=0.012). The proportion of variance in hip BMD explained by PYY cycle mean was 8.6% (R(2)=0.109, p=0.033). The proportion of variance in total body BMD explained by body weight and E1G cycle mean was 21.9% (R(2)=0.257, p=0.003). CONCLUSION PYY, mean E1G and body weight are associated with BMD in premenopausal exercising women. Thus, elevated PYY and suppressed estrogen concentrations are associated with, and could be directly contributing to, low BMD in exercising women with amenorrhea, despite regular physical activity.
Medicine and Science in Sports and Exercise | 2014
Jenna C. Gibbs; Aurelia Nattiv; Michelle T. Barrack; Nancy I. Williams; Mitchell J. Rauh; Jeanne F. Nichols; Mary Jane De Souza
UNLABELLED The cumulative effect of the female athlete triad (Triad) risk factors on the likelihood of low bone mineral density (BMD) in exercising women is unclear. PURPOSE This study aimed to determine the risk of low BMD in exercising women with multiple Triad risk factors. METHODS We retrospectively examined cross-sectional data from 437 exercising women (mean ± SD age of 18.0 ± 3.5 yr, weighed 57.5 ± 7.1 kg with 24.5% ± 6.1% body fat) obtained at baseline from 4 prospective cohort studies examining Triad risk factors. Questionnaires were completed to obtain information on demographic characteristics, self-reported eating attitudes/behaviors, menstrual function, sport/activity participation, and medication use. Height and body weight were measured. BMD was measured using dual energy x-ray absorptiometry. Low BMD was defined as z-scores of <-1 and ≤-2. Chi-square tests were performed to determine the percentage of women with low BMD who met the criteria for individual (current oligo/amenorrhea, late menarche, low body mass index (BMI), elevated dietary restraint, lean sport/activity participation) or multiple (2, 3, 4, or 5) Triad risk factors. RESULTS Late menarche and low BMI were associated with the highest percentage of low BMD (z-score < -1), 55% and 54%, respectively, and low BMD (z-score ≤-2), 14% and 16%, respectively. The percentage of participants with low BMD (z-score < -1 and ≤-2) increased from 10% to 62% and from 2% to 18%, respectively, as women met the criteria for an increasing number of Triad risk factors. CONCLUSIONS A cumulative number of Triad risk factors were associated with an increased risk of low BMD, suggesting a dose-response association between the number of Triad risk factors and BMD in exercising women. Further research should be conducted to develop a user-friendly algorithm integrating these indicators of risk for low BMD in exercising women (particularly factors associated with low BMI/body weight, menstrual dysfunction, lean sport/activity participation, and elevated dietary restraint).
Medicine and Science in Sports and Exercise | 2013
Jenna C. Gibbs; Nancy I. Williams; Rebecca J. Mallinson; Jennifer L. Reed; Ashley D. Rickard; Mary Jane De Souza
INTRODUCTION Dietary restraint (DR) is a key eating behavior associated with menstrual disturbances (MD) in exercising women. However, the association between DR and energy availability (EA) has not been examined. PURPOSES The objective of this study is 1) to compare EA in women when categorized by DR score, to include an evaluation of the frequency of women with low EA, and 2) to compare the distribution of subclinical and clinical MD between DR groups. METHODS Exercising women (23 ± 4 yr; body mass index, 21.1 ± 1.9 kg·m; and exercise volume, 333 ± 198 min·wk) were retrospectively categorized by DR score into two groups: 1) women with high DR (n = 30) and 2) women with normal DR (n = 56). DR scores were obtained from the Three-Factor Eating Questionnaire. High DR score was defined as ≥13. Body composition was measured using dual-energy x-ray absorptiometry. EA was defined as energy intake - exercise energy expenditure per kilogram lean body mass (LBM). Low EA was defined as <30 kcal·kg LBM. Menstrual status was determined using daily urinary samples assayed for reproductive hormones. RESULTS EA was lower in the high DR versus the normal DR group (35.0 ± 12.9 vs 42.0 ± 12.9 kcal·kg LBM, P = 0.018). There was no difference (P = 0.866) in frequency of low EA between DR groups. There was a greater frequency of MD (amenorrhea, oligomenorrhea, anovulation, or luteal phase defect) in the high DR group (21/28, 75.0%) versus the normal DR group (24/47, 51.1%) (χ = 4.2, P = 0.041). CONCLUSION Our findings demonstrate that exercising women with high DR exhibited lower EA and a greater frequency of MD (subclinical and clinical) compared with women with normal DR. However, high DR was not associated with low EA in exercising women.
Journal of Sports Sciences | 2016
Karsten Koehler; Neele R. Hoerner; Jenna C. Gibbs; Christoph Zinner; Hans Braun; Mary Jane De Souza; Wilhelm Schaenzer
ABSTRACT Low energy availability, defined as low caloric intake relative to exercise energy expenditure, has been linked to endocrine alterations frequently observed in chronically energy-deficient exercising women. Our goal was to determine the endocrine effects of low energy availability in exercising men. Six exercising men (VO2peak: 49.3 ± 2.4 ml · kg−1 · min−1) underwent two conditions of low energy availability (15 kcal · kg−1 fat-free mass [FFM] · day−1) and two energy-balanced conditions (40 kcal · kg−1 FFM · day−1) in randomised order. During one low energy availability and one balanced condition, participants exercised to expend 15 kcal · kg−1 FFM · day−1; no exercise was conducted during the other two conditions. Metabolic hormones were assessed before and after each 4-day period. Following both low energy availability conditions, leptin (−53% to −56%) and insulin (−34% to −38%) were reduced (P < 0.05). Reductions in leptin and insulin were independent of whether low energy availability was attained with or without exercise (P > 0.80). Low energy availability did not significantly impact ghrelin, triiodothyronine, testosterone and IGF-1 (all P > 0.05). The observed reductions in leptin and insulin were in the same magnitude as changes previously reported in sedentary women. Further research is needed to understand why other metabolic hormones are more robust against low energy availability in exercising men than those in sedentary and exercising women.
Physical Therapy | 2014
Lora Giangregorio; Thabane L; Jonathan D. Adachi; Maureen C. Ashe; Robert Bleakney; Braun Ea; Angela M. Cheung; Fraser La; Jenna C. Gibbs; Keith D. Hill; Hodsman Ab; David L. Kendler; N. Mittmann; S. Prasad; Samuel Scherer; John D. Wark; Alexandra Papaioannou
Background Our goal is to conduct a multicenter randomized controlled trial (RCT) to investigate whether exercise can reduce incident fractures compared with no intervention among women aged ≥65 years with a vertebral fracture. Objectives This pilot study will determine the feasibility of recruitment, retention, and adherence for the proposed trial. Design The proposed RCT will be a pilot feasibility study with 1:1 randomization to exercise or attentional control groups. Setting Five Canadian sites (1 community hospital partnered with an academic center and 4 academic hospitals or centers affiliated with an academic center) and 2 Australian centers (1 academic hospital and 1 center for community primary care, geriatric, and rehabilitation services). Participants One hundred sixty women aged ≥65 years with vertebral fracture at 5 Canadian and 2 Australian centers will be recruited. Intervention The Build Better Bones With Exercise (B3E) intervention includes exercise and behavioral counseling, delivered by a physical therapist in 6 home visits over 8 months, and monthly calls; participants are to exercise ≥3 times weekly. Controls will receive equal attention. Measurements Primary outcomes will include recruitment, retention, and adherence. Adherence to exercise will be assessed via calendar diary. Secondary outcomes will include physical function (lower extremity strength, mobility, and balance), posture, and falls. Additional secondary outcomes will include quality of life, pain, fall self-efficacy, behavior change variables, intervention cost, fractures, and adverse events. Analyses of feasibility objectives will be descriptive or based on estimates with 95% confidence intervals, where feasibility will be assessed relative to a priori criteria. Differences in secondary outcomes will be evaluated in intention-to-treat analyses via independent Student t tests, chi-square tests, or logistic regression. The Bonferroni method will be used to adjust the level of significance for secondary outcomes so the overall alpha level is .05. Limitations No assessment of bone mineral density will be conducted. The proposed definitive trial will require a large sample size. Conclusions The viability of a large-scale exercise trial in women with vertebral fractures will be evaluated, as well as the effects of a home exercise program on important secondary outcomes.