Hot off the press: New research
Hausswirth, C., & Le Mem, L. (2011). Physiological and nutritional aspects of post-exercise recovery: Specific recommendations for female athletes. Sports Medicine, 41(10): 861-882.
This literature review presents the current knowledge on post-exercise recovery with a special focus on female athletes/exercising women and how metabolic, thermoregulatory or inflammation and repair processes may differ from those observed in males. Particular attention is given to recovery strategies that may be the most pertinent to the design of training programmes for female athletes and exercising women, in order to optimize the physiological adaptations sought for improving performance and maintaining health. Of specific interest to our readers is the nutritional information in this review. Glycogen (i.e. carbohydrate) stores are depleted during endurance exercise (>90min) and micro-damage also occurs in the muscle. Thus, exercising women must consume carbohydrates to maximise repletion of glycogen stores and also protein for tissue building and repair , as soon as possible after exercise (i.e. within 30min). Yoghurt and fruit is a good option here! It is also important to consume an adequate intake of fat in the overall diet (25-30%). Good examples of nutritious dietary fats include avocados, nuts, seeds and olive oil.
Miller, S.M., Kukuljan, S., Turner, A.I., van der Pligt, P., & Ducher, G. (2012). Energy deficiency, menstrual disturbances and low bone mass: What do exercising Australian women know about the Female Athlete Triad? International Journal of Sport Nutrition and Exercise Metabolism, 22, 131 -138.
This observational study investigated the knowledge, attitudes and behaviours of regularly exercising adult women in Australia towards eating patterns, menstrual cycles, and bone health. Respondents participated in a wide range of sports and exercise activities. Few women are aware of the detrimental effects of menstrual disturbances on bone health. Indeed, only 10% accurately identified the key components of the Triad, 45% did not think that amenorrhea could affect bone health and 22% of those involved in lean-build sports reported that they would not seek advice or management if they experienced amenorrhea. The results highlight the importance for educational programmes to improve awareness and understanding to prevent the Female Athlete Triad and ensure exercising women experiencing amenorrhea seek appropriate management.
Loucks, A. B., Kiens, B., & Wright, H. H. (2011). Energy availability in athletes. Journal of Sports Sciences, 29(sup1), S7-S15.
Anne Loucks is a pioneering researcher who has investigated the effect of low energy availability on menstrual function and bone health in women. This paper complements one of her earlier reviews* presenting conclusive evidence that many female athletes are energy deficient at levels sufficient to impair their health. However, she also emphasised that energy balance is often not the objective of training for female athletes who aspire to reduce body weight or body fat to achieve performance objectives. This review goes on to argue that the concept of energy availability is more useful than that of energy balance for managing female athletes diets. Summaries of recent research on the existence, etiology, and clinical consequences of low energy availability are presented. The evidence that hunger is not a reliable indicator for energy and macronutrient needs in female athlete with high energy expenditures and the implications of this research for managing the diets of athletes is also discussed.
*Loucks, A. B. (2004). Energy balance and body composition in sports and exercise. Journal of Sports Science, 22(1), 1-14.
Sundgot-Borgen, J., & Torstveit, M. K. (2010). Aspects of disordered eating continuum in elite high-intensity sports. Scandinavian Journal of Medicine & Science in Sports, 20, 112-121.
Jorunn Sundgot-Borgen and Monica Torstveit are Norwegian researchers who have made a significant contribution to the international body of literature pertaining to disordered eating, eating disorders, menstrual disturbances and bone mineral density in elite female athletes. In this review they discuss the definitions in the continuum of disordered eating, longitudinal trends in prevalence, risk factors, health and performance consequences and recommendations for treatment, management and prevention. The main focus group is athletes who participate in high-intensity sports (e.g. gymnastics, rowing, squash, swimming, karate, middle distance running and skiing).
Other Relevant Research
Loucks, A. B. (2003). Energy availability, not body fatness, regulates reproductive function in women. Exercise and Sport Sciences Reviews, 31(3), 144-148.
Informative summary outlining how research on the etiology of amenorrhea in exercising women has evolved. Loucks reviews why the body composition and exercise stress hypotheses fail to explain the mechanism of menstrual disturbances in exercising women and explains the evidence supporting the energy availability hypothesis. The metabolic and endocrine signs of energy deficiency are common in female athletes with menstrual disturbances and 30kcal.kgFFM.day-1 appears to be the energy availability threshold by which normal reproductive function and skeletal health is preserved. Loucks suggests screening women for luteal phase length may be a convenient way to identify those who need to take care to avoid falling below this threshold to maintain normal reproductive function.
De Souza MJ, Van Heest J, Demers LM, Lasley BL. Luteal phase deficiency in recreational runners: Evidence for a hypometabolic state. J Clin Endocrinol Metab. 2003;88(1):337-46.
Sedentary and exercising (>2hrs/wk) ovulatory women and exercising women with luteal phase defects (LPD) were investigated in this prospective study to evaluate the effect of LPD on metabolic hormones. Exercising women with LPD had lower thyroid, insulin and leptin levels suggesting a compromised metabolic state, similar to that found in amenorrheic female athletes. Research shows a high percentage of exercising females have an inconsistent menstrual cycle (see De Souza et al, 1998). Therefore, short-term negative energy balance may lead to fluctuations in metabolic state. The authors explain that compromised menstrual function in exercising women occurs to conserve energy (i.e. lower total energy expenditure) in an attempt to restore energy balance.