A fellow psychiatry professor came in for treatment after overhearing me talk about an ADHD case study at a party. "I think you described me," he said, and launched into a highly intellectual rendition of his own history. Charles, I'll call him, was the classic absentminded professor, wearing glasses and unkempt tweed, and he knew a lot more about psychiatry than I did.
The twist to Charles's story is that he had been a marathon runner who had blown out his knee. He became depressed when he was forced to set aside his passion. That's also when he noticed the symptoms of ADHD. He explained that he would have a tantrum if his girlfriend interrupted his writing, or yank the phone out of the wall if it rang while he was trying to concentrate. He was slipping out of touch with his friends. He fit the profile, and we decided to put him on ADHD medication. It helped.
Charles was on antidepressants when he came to see me, but once he finished physical therapy and started training again, he dropped them because he felt so much better. As he closed in on his old fitness level, he became convinced that the ADHD medication was holding back his performance.
He decided to try a few days without the ADHD medication, and he found that as long as he was training, he could focus. Looking back on it, we recognized that his attention hadn't hampered him before because he had always been a serious runner. Without a steady diet of exercise during his injury, he'd been unable to control his attention the way he needed to. Exercise had a powerful effect.
Most people instinctively know that exercise burns off energy. Any teacher who has dealt with a hyperactive child will tell you that kids are much calmer after recess. Being calmer and more focused is one of the happy consequences of exercise. Given the leading role of dopamine and norepinephrine in regulating the attention system, the broad scientific explanation for how exercise tempers ADHD is that it increases these neurotransmitter levels. It does so immediately. With regular exercise, we can raise the baseline levels of dopamine and norepinephrine by spurring the growth of new receptors in certain brain areas.
In the brain stem, balancing norepinephrine in the arousal center also helps. "Chronic exercise improves the tone of the locus coeruleus," says Amelia Russo-Neustadt, M.D., Ph.D., a neuroscientist and psychiatrist at California State University. The result is that we're less prone to startle or to react out of proportion to any given situation. We feel less irritable.