tDCS for Increasing Exercise Adherence in Depressed Individuals

Exercise adherence is a significant public health problem. Affective experiences during exercise predict long-term physical activity (PA) levels. Therefore, approaches to improving the affective experience of exercise are both important and likely to have high impact. This may be particularly true among individuals with elevated depressive symptoms due to their tendency toward more negative and less positive affect. tDCS is a noninvasive brain stimulation approach with a growing body of literature supporting its effects on cognitive and emotional processing in varied populations, including some support for those with depression. In addition, there is recent increased interest in utilizing tDCS in the context of exercise (see above) and in obesity prevention. While the effects of tDCS on behavioral and cognitive functioning are still developing, promising findings have emerged for tDCS used in repeated combination with a behavioral or cognitive intervention. Given that tDCS is relatively safe, inexpensive, and portable, individuals who struggle with enjoying exercise could be afforded a practical option for increasing and maintaining physical activity levels.

We propose to conduct a pilot randomized controlled trial of tDCS versus sham delivered 3x/week for 8 weeks in the context of a supervised aerobic exercise (AE) program among 72 low-active individuals with elevated depressive symptoms. Follow-up assessments will be conducted at end of treatment, 3, and 6 months.

Inclusion criteria

• be between 18 and 65 years of age
• be low active
• have elevated levels of depressive symptoms
• interested in starting an exercise program in the next month

Exclusion criteria

• history of mania or hypomania
• current psychotic disorder
• current DSM-5 diagnosis of an eating disorder
• DSM-5 moderate and severe substance use disorder
• current suicidality or homicidality
• current DSM-5 diagnosis of major depressive disorder that is not currently being treated with pharmacotherapy or psychotherapy
• physical disabilities or medical problems that would prevent participation in moderate intensity exercise or may be contraindicated for tDCS
• current pregnancy or intent to become pregnant during the next 8 weeks
• pacemaker or metal implanted in the cranial cavity