Nancy I. Williams

 Nancy Williams

Professor of Kinesiology and Physiology, and Head of Department, Kinesiology

Contact Information

276 Recreation Building
The Pennsylvania State University
University Park PA 16802


(fax) 814-865-1275


Sc.D., 1992, Applied Physiology, Boston University

Research Interests

Exercise physiology, women’s health and exercise, effects of exercise and diet on the menstrual cycle, gastrointestinal peptides and food intake, neuroendocrinology, metabolism, skeletal physiology


  • Women’s health and exercise with an emphasis on the female athlete triad
  • Interactions between energy balance and menstrual cycle physiology in exercising women
  • Effects of food intake and exercise on gut peptides and metabolic signals
  • Effects of psychosocial stressors on reproductive function 

Selected Publications

Williams NI, Statuta S, Austin A. Female athlete triad: Future directions for energy availability and eating disorder research and practice. Clin Sports Med. 2017 Oct; 36(4):671-686.

Koehler K, De Souza MJ, Williams NI. Less-than-expected weight loss in normal-weight women undergoing caloric restriction and exercise is accompanied by preservation of fat-free mass and metabolic adaptations. Eur J Clin Nutr. 2017 Mar;71(3):365-371.

Williams NI, Etter CV, Lieberman JL. The science of healthy menstruation in exercising women. Kinesiology Review 2017, 6(1): 78-90.

Mallinson RJ, Williams NI, Gibbs JC, Koehler K, Allaway HC, Southmayd E, De Souza MJ. Current and past menstrual status is an important determinant of femoral neck geometry in exercising women. Bone. 2016 Jul;88:101-112

Reed JL, De Souza MJ, Mallinson RJ, Scheid JL, Williams NI. Energy availability discriminates clinical menstrual status in exercising women.J Int Soc Sports Nutr. 2015 Feb 19;12:11.

Williams NI, Leidy HJ, Hill BR, Lieberman JL, Legro RS, De Souza MJ. Magnitude of daily energy deficit predicts frequency but not severity of menstrual disturbances associated with exercise and caloric restriction. Am J Physiol Endocrinol Metab. 2015 Jan 1;308(1):E29-39.

De Souza MJ, Williams NI, Nattiv A, Joy E, Misra M, Loucks AB, Matheson G, Olmsted MP, Barrack M, Mallinson RJ, Gibbs JC, Goolsby M, Nichols JF, Drinkwater B, Sanborn CB, Agostini R, Otis CL, Johnson MD, Hoch AZ, Alleyne JM, Wadsworth LT, Koehler K, VanHeest J, Harvey P, Weiss Kelly AK, Fredericson M, Brooks GA, O'Donnell E, Callahan LR, Putukian M, Costello L, Hecht S, Rauh MJ, McComb J. Misunderstanding the Female Athlete Triad: Refuting the IOC Consensus Statement on Relative Energy Deficiency in Sport (RED-S). Br J Sports Med. 2014 JFeb;48(4):289