Assets of Exercise
Highlights from the International Society for Bipolar Disorders Conference Posters and Presentations, Chicago, June 22-25, 2023
Ben Goldstein of the University of Toronto gave a plenary talk on the benefits of exercise.
He found poor aerobic fitness in 19 of 20 young bipolar patients. They had low cerebral blood flow in proportion to the severity of their exhaustion after exercise. He noted the importance of stressing an endpoint of fitness for exercise rather than weight loss. Using an exercise coach and running with family and friends was helpful in motivating patients for consistent exercise.
Exercise Improves Fitness, May Help Reduce Cocaine Use
In studies of rodents, running on a wheel reduces cocaine self-administration. A recent study by Richard de la Garza and colleagues investigated whether running or walking on a treadmill can reduce cocaine cravings and use in humans. In the study of 24 participants who had been using cocaine an average of 19.7 years, participants were randomized to run, walk, or sit for 30 minutes three times per week for four consecutive weeks. After exercising, the participants reported having less craving for cocaine. Fitness measures such as body weight and resting heart rate improved in both walkers and runners. While not statistically significant, by the end of the study there was a trend indicating that exercise improved abstinence from cocaine and decreased daily craving for cocaine.
Editor’s Note: Exercise Increases brain-derived neurotrophic factor (BDNF) and neurogenesis. In rodents, cocaine is associated with decreases in BDNF in the frontal cortex, and injecting BDNF there decreases cocaine seeking. Whether this BDNF effect or the general effects of exercise on mood and conditioning account for these positive cocaine effects remains to be ascertained.
BDNF Related to Cognition and Fitness in Men with Coronary Artery Disease
At the 51st Annual Meeting of the National Institute of Mental Health’s New Clinical Drug Evaluation Unit (NCDEU) in 2011, Walter Swardfager and colleagues from Toronto, Ontario presented a study indicating that brain-derived neurotrophic factor (BDNF) concentrations in blood are associated with cognitive performance and cardiopulmonary fitness in people with coronary artery disease.
In 88 mostly male subjects with a mean age of 63 years, cardiopulmonary fitness was directly correlated with BDNF in blood as well as higher scores of cognition on two tests, the mini mental status exam and the digit symbol coding task. The investigators concluded that better fitness, psychomotor processing speed, and overall cognition were consistent with a hypothesis that BDNF protects midbrain dopaminergic neurons against inflammatory neurodegenerative processes.
Blood levels of interleukin 6, a measure of inflammatory cytokines, were associated with lower mini mental status scores in a multivariate analysis that controlled for BDNF levels.
Editor’s note: BDNF appears to be necessary for long-term learning and memory. Meta-analyses indicate that BDNF levels are low in depression and improve with euthymia. Many mood stabilizers including lithium, valproate, carbamazepine, and lamotrigine and most types of antidepressants are able to increase BDNF. The current findings linking BDNF with better cardiopulmonary fitness and cognition continue to emphasize the potential importance of BDNF beyond its role as a marker for depression.
In BNN Volume 12, Issue 3 from 2008, we reported on the data of Schmidt and Duman, which indicated that BDNF administered in a subcutaneous minipump is able to reverse many depressive-like behaviors in an animal model of depression, suggesting that even peripheral BDNF may have a role in the central nervous system.
