According to the National Health Interview Survey, the prevalence of ADHD in children 4 to 17 years of age was 10.2 percent in 2015-2016 (1). ADHD is a neurological condition that affects brain functions important for school and work success.
The condition most noticeably impacts a group of cognitive functions known collectively as executive functioning. These include inhibition, working memory, and cognitive flexibility. Inhibition is the ability to resist distraction and maintain focus. Working memory is the ability to hold and manipulate information currently in use. The last area, cognitive flexibility, is the opposite of mental rigidness. According to the most recent edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), there are three types of ADHD: hyperactive-impulsive, inattentive (previously denoted as ADD), or combined type.
Children with the hyperactive type may act as if they are driven by a motor and often have poor impulse control. They tend to find it challenging to sit still in a traditional classroom. Children with inattentive ADHD are better at blending in because they can sit still. But as school work becomes more demanding, their ADHD symptoms often become more obvious. They are easily distracted, forgetful, and frequently daydream. Combined type ADHD, as its name suggests, is a combination of the hyperactive and inattentive types.
ADHD symptoms negatively impact executive functioning, leading to weak impulse control, poor decision making, and difficulty shifting from one task to another. In turn, the child becomes frustrated; this often manifests as behavior problems and emotional dysregulation.
Treatment, therefore, is essential in reducing the child’s frustration and increasing their daily functioning. Evidence suggests that a combination of treatments—including medication, behavioral therapy, and dietary changes—is often most effective. Many studies have also pointed to one particularly protective solution: exercise.
In one study, researchers randomly assigned 8- and 9-year-olds to a nine-month after-school fitness program (FITKids) or to a wait-list control group (2). All participants performed cognitive tasks that assessed attentional inhibition and cognitive flexibility while measuring brain electrical activity before the intervention (fitness program/wait list) and after. Researchers focused on a specific brainwave signature that has been associated with attention, working memory, and cognitive processing speed.
The fitness group improved more than the wait-list group on accuracy and speed on the executive function tasks. Notably, the brainwave signature for focus and attention was more intense in the fitness group than the control group; it was significantly greater in magnitude and arrived faster for the fitness group.
There are many studies vouching for the “exercise prescription” for ADHD. Another study, published in the Journal of Attention Disorders, showed that moderate to vigorous exercise for 45 minutes, three times a week, improved cognitive functioning and behavior in children with ADHD (3). They were cognitively quicker and demonstrated more efficient information processing.
One study showed similar results but added an important consideration: sex. Many parents, doctors, and teachers will tell you that in general, boys and girls demonstrate their ADHD symptoms differently. According to the findings of this study, boys may require more vigorous exercise than girls to collect the benefits of exercise on attention (3).
In sum, these results indicate that exercise can increase focus and accelerate cognitive processing in children with ADHD.
Why Would Exercise Improve ADHD Symptoms?
- Exercise is an excellent outlet for stress, which exacerbates symptoms.
- Exercise can absorb anxious energy and alleviate anxiety. Anxiety often co-occurs with ADHD, further disturbing attentional processes and other cognitive abilities.
- Exercise increases chemicals in the brain called brain-derived neurotrophic factors. These neurotransmitters are crucially involved in learning and memory. Some studies have suggested that people with ADHD have a shortage of these nurturing chemicals.
- Exercise targets many of the same neurotransmitters stimulated by medical treatments for ADHD.
- For those with the hyperactive type, exercise can be a useful way to release excessive energy and “fidgetiness.”
- In general, higher levels of fitness lead to a healthier brain and body. Indeed, an unhealthy body can severely interrupt cognitive faculties such as attention.
What Kind of Exercise?
Many children who struggle with ADHD have low self-esteem and self-confidence. I would advise parents to stay away from highly competitive sports that require challenging schedules and a very fast pace—unless the child is naturally talented or particularly driven. Sports such as cross-country might be best for children and teens with ADHD. The type of sport can vary; most important is to find something your child enjoys, and that you encourage and support them to routinely engage in it.
Treatment decisions can be difficult, especially given the side effects of medications and cost and time commitment needed for behavioral therapy. But regardless of the chosen treatment, exercise can be an excellent therapeutic adjunct, with potentially big effects.
(1) Xu, Guifeng et al. (2018). Twenty-Year Trends in Diagnosed Attention-Deficit/Hyperactivity Disorder Among US Children and Adolescents, 1997-2016. JAMA Network Open, 1(4):e181471.
(2) Hillman, C. H. et al. (2014). Effects of the FITKids Randomized Controlled Trial on Executive Control and Brain Function. Pediatrics, 134(4), e1063-1071.
(3) Ratey J. J. Spark: The Revolutionary New Science of Exercise and the Brain. New York, NY: Little, Brown and Company, 2008.