Exercise training reduces alcohol consumption but does not affect HPA-axis activity in heavy drinkers

Background It has been suggested that physical exercise could have potential beneficial effects in substance abusers, which are based on both physiological and psychological theories. Although a few studies have examined the effect of exercise on alcohol intake and fitness in individuals with alcohol use disorders (AUDs), there is a gap in the literature concerning the physiological and biochemical mechanisms that could be affected by physical exercise in this population. Purpose The purpose of the present study was to examine physiological and biochemical responses to exercise after an 8-week supervised exercise training (ET) intervention in heavy drinkers. The investigation was mainly focused on the relationship among exercise, opioids, the hypothalamic-pituitary-adrenal axis (HPA) activity and heavy alcohol drinking. Methods Eleven (Age: 30.3 ± 3.5 yrs; Body Mass Index: 28.4 ± 0.86 kg/m2) male heavy drinkers volunteered to participated in an 8-week supervised intervention of moderate intensity exercise (50–60% of Heart Rate Reserve). All participants were exhibiting low physical activity and used to drink heavily. Before intervention, the participants were asked to record their daily alcohol intake without changing their physical activity levels for 4 weeks (control condition). During the 8-week supervised ET intervention, participants were recording their daily alcohol intake and were motivated to increase gradually the duration and frequency of ET. Blood samples were collected prior to and after 4 weeks of the control condition, the day before the beginning of the ET intervention, and at the end of the 4th and 8th week of ET intervention. Blood samples were analyzed for β-E, epinephrine, norepinephrine, adrenocorticotropin, cortisol, gamma-glutamyl transferase (γ-GT), aspartate transaminase and alanine transaminase. Physiological and alcohol-related indices were also examined. Results The 8-week supervised ET intervention resulted in reduced alcohol consumption, reduced γ-GT levels, and fitness improvement in heavy drinker. ET intervention did not significantly change the hormonal responses. Conclusion The results indicate that physical exercise could act as a healthy habit that can help individuals with AUDs reduce alcohol intake and improve health status; however, this is not related with changes in hormones associated with the HPA-axis. © 2017 Elsevier Inc.