Effects of Intensive Training on Prolactin Responses to Submaximal Exercise in Males

The purpose of this study was to determine if serum prolactin responses to submaximal exercise were affected by 8 weeks of intensive training (5 cl/wk, 90 min/d 65-200% V02max). Nine males performed 90 minute continuous exercise bouts (cycle ergometry; 65% V02 max) at the end of 1, 4, and 8 weeks of training. Blood samples were obtained pre-training, and pre-, post-exercise. Significant differences were not seen in pre- and post-exercise prolactin levels at weeks 1 and 4. However, at week 8 the post-exercise prolatin was significantly greater than the pre-exercise levels (6.8 ± 0.9 vs 3.8 ± 1.0 ng·ml-1; P-1, respectively). The findings suggest intensive training results in a relative augmentation of the post-exercise prolactin response; however, this effect seems to be due primarily to the training induced lowered resting prolactin levels