Anne B. Loucks, Ph.D.

     The main purpose of this laboratory is to investigate the integrative processes that regulate the human reproductive system. Our interest in this subject is motivated by the high prevalence of menstrual disorders, including amenorrhea and luteal suppression, in physically active women, and by the progressive and apparently irreversible skeletal demineralization that occurs in amenorrheic women as a result of their low estrogen levels. We are especially interested to learn whether these menstrual disorders are caused by exercise itself or by some other factor, such as under-nutrition, in the lifestyle of physically active women; and to identify other factors, such as adiposity, parity, age, gender, or genetics that may modulate these effects. We further seek to discover the metabolic and endocrine mechanisms that mediate the influence of these factors on reproductive function, and to develop practical means for preventing and reversing these menstrual disorders.

     Another purpose of this laboratory is to investigate the integrative processes that regulate metabolic responses to exercise. Of particular interest are the endocrine mechanisms that mobilize metabolic fuels during exercise.

Selected References:

• Hilton, L. and A.B. Loucks. Low Energy Availability, Not Exercise Stress, Suppresses the Diurnal Rhythm of Leptin in Healthy Young Women. Am J Physiol Endocrinol Metab 278: E43-E49, 2000.

• Loucks, A.B., Exercise training in the normal female: Effects of exercise stress and energy availability on metabolic hormones and LH pulsatility. In: Sports Endocrinology, M. Warren and N. Constantini (Eds), Humana Press, Totowa, NJ, pp 165-180, 2000.

• DeSouza, M.J., B.E. Miller, A.B. Loucks, A.A. Luciano, L.S. Pescatello, G.C. Campbell, and B.L. Lasley. High Frequency of Luteal Phase Deficiency and Anovulation in Recreational Women Runners: Blunted Elevation in Follicle-Stimulating Hormone Observed During Luteal-Follicular Transition. J Clin Endocrinol Metab 83(12): 4220-4232, 1998.

• Loucks, A.B. and M. Verdun. Slow Restoration of LH Pulsatility by Refeeding in Energetically Disrupted Women. Am. J. Physiol 275 (Regulatory Integrative Comp. Physiol.), R1218-R1226, 1998.

• Loucks, A.B., Verdun, M., and E.M. Heath. Low Energy Availability, Not Stress of Exercise, Alters LH Pulsatility in Exercising Women. J Appl Physiol 84(1):37-46, 1998.

• Thuma, J., R. Gilders, M. Verdun and Loucks, A.B. Circadian Rhythm of Cortisol Confounds Cortisol Responses to Exercise: Implications for Future Research. J Appl Physiol 78:1657-1664, 1995.