Effect of menstrual cycle phase on carbohydrate supplementation during prolonged exercise to fatigue

1 Department of Physical Therapy Education, Elon College, Elon College, North Carolina 27244; and 2 Department of Exercise Science and Sport Studies, Rutgers University, New Brunswick, New Jersey 08903 The effects of menstrual cycle phase and carbohydrate (CHO) supplementation were investigated during prolonged exercise. Nine healthy, moderately trained women cycled at 70% peak O 2 consumption until exhaustion. Two trials were completed during the follicular (Fol) and luteal (Lut) phases of the menstrual cycle. Subjects consumed 0.6 g CHO · kg body wt 1 · h 1 (5 ml/kg of a 6% CHO solution every 30 min beginning at min 30 of exercise) or a placebo drink (Pl) during exercise. Time to exhaustion during CHO increased from Pl values ( P