“It’s disappointing there were no acute effects on cravings in line with other studies,” Adrian Taylor, PhD, professor of health services research, Plymouth University Peninsula Schools of Medicine and Dentistry, United Kingdom, told Medscape Medical News. “But the study doesn’t dismiss the possibility that various forms of exercise may chronically influence alcohol use,” said Dr Taylor, who was not involved in the study.
In contrast to the current study, Dr Taylor and colleagues conducted a study that included 20 abstaining alcohol drinkers in which the researchers found significant reductions in the urge to drink after a 15-minute bout of low-intensity treadmill walking. Exercise also reduced attentional bias to alcohol-related images. These results suggest that regular exercise “may reduce interest in drinking and related cues,” the authors concluded in their article.
“The novelty of the study is the use of resistance exercise – as opposed to walking or cardiovascular exercise, which is the modality typically used in this line of research – with this sample of hazardous drinkers,” Panteleimon Ekkekakis, PhD, associate professor, Department of Kinesiology, Iowa State University, in Ames, told Medscape Medical News. “I am sure that the authors would agree that this was a preliminary or pilot study, limited by the small sample (of only 14) and the fact that the intervention (resistance exercise) was only applied once. So, clearly, the study does not lend itself to proper statistical analyses, and any conclusions should be viewed with caution,” said Dr Ekkekakis, who was not involved in the study.
“Nevertheless, it is interesting that the participants felt better with exercise, and their scores on the ‘urge to drink’ questionnaire dropped by 6 points after exercise vs 3 points after watching a video. Presumably, after getting more accustomed to the exercise and improving their fitness, the results may improve further,” said Dr Ekkekakis.
He noted that the potential of exercise to aid in the treatment of addictions is a “rapidly evolving” line of research. “Previous studies have been done in a variety of settings, including cigarette smokers trying to quit, compulsive chocolate eaters, and individuals in treatment programs for opioid addictions.
All of these studies were based on the “hedonic substitution” hypothesis, according to which exercise can produce a transient increase in pleasure that can be harnessed to pull individuals away from their problem behaviors (ie, substituting the unhealthy pleasure with a healthy one),” Dr Ekkekakis explained.
This hypothesis has received support from findings in animal studies, he indicated. In those studies, when rodents that were addicted to amphetamines or alcohol were given the opportunity to use a running wheel, their addictive behaviors gradually lessened, and eventually they switched to the running wheel.
The problem is that for hedonic substitution to work with people who suffer with addictions, exercise must be pleasant.
“However, in reality, many individuals with addictions may face considerable barriers, including a history of sedentary living, low cardiorespiratory fitness, high body mass, and other mental health problems, such as anxiety or depression. So making exercise not only pleasant but pleasant enough to match or surpass the pleasure that someone can derive from an addictive substance is far from easy,” Dr Ekkekakis said.
“So the challenge that this line of research faces is developing exercise programs that can rapidly and reliably make participants experience exercise as pleasant and enjoyable,” he added.
The study had no commercial funding. The authors have disclosed no relevant financial relationships.
Am J Addict. Published online September 26, 2016