Influence of Exercise Training on Blood Prolactin Levels (2009)
Undergraduates: Stephanie Caudle, Amy Lane
Faculty Advisor: Anthony Hackney
Department: Exercise & Sport Science
The purpose of this investigation was to determine the influence of exercise training on resting blood prolactin (PRL, a "stress hormone") levels, specifically a three-day intensive microcycle of exercise training. Ten endurance trained males completed a training protocol consisting of three consecutive days of 60-minute exercise training sessions on a cycle ergometer at ~75% of their VO2peak. This microcycle was designed to elicit similar physiological effects as seen within the Overtraining Syndrome. Pre- and post-exercise blood samples were analyzed for PRL in order to determine the effect of exercise on basal, resting levels of PRL. Results indicate that resting PRL levels were significantly increased (p<0.01) at 24-hr following the third training session in comparison to resting levels 24-hr following the first and second training sessions as well as basal, resting blood levels prior to the study. The relationship between blood PRL levels and the increased training stress of the microcycle suggest that PRL has potential as a biomarker of the Overtraining Syndrome.