Effects of long-term exercise bouts on levels of endogenous morphinomimetic hormones

Abstract

Statement of the Problem. The problem of this study was to investigate the relationship between long-term exercise bouts and its effect on sera endorphin levels in selected human subjects. Procedure. Ten subjects performed daily exercise bouts on treadmills in the Human Performance Laboratories, Department of Health and Physical Education, Texas A&M University, for a period of 4 days. A pre-exercise blood sample of approximately 5 ml and a post-exercise blood sample of approximately 5 ml were taken from each subject each day. The study resulted in each subject having given 8 samples of sera which were then analyzed by the Veterinary Pharmacology Laboratories in the College of Veterinary Medicine at Texas A&M University. The samples were analyzed according to set procedures. It was hypothesized that endorphin levels would increase from pre-exercise blood samples to post-exercise blood samples. An analysis of variance procedure was performed to investigate the effect that exercise has on levels of endorphin in blood sera. The results indicated a significant difference from pre to post sera samples ((alpha) = .05). A second hypothesis involving cyclical differences between post sample values of the preceding day and pre sample values of the following day was tested. The results failed to reject the hypothesis stating that there is no significant difference between the two values in a cycle. Further data base is necessary before definitive conclusions can be established. Therefore, the investigator has opted to suspend judgement until such data base is established.