If you are reading this, you already know the basics. You are probably aware that there are a few silver bullets when it comes to feeling better: eating right, getting enough sleep, meditation, and exercise are always on the list. The wonders of nutrition, restorative rest, and mindfulness are everywhere–and of course, we know how good exercise is for keeping lean, building strength, promoting sleep, and burning off stress. But there is something about exercise that you may not know. It is one the best investments of our time for general well-being and happiness for another reason: It actually makes our brains work better. The biochemistry of the brain is fragile and affected by almost everything we can think of. Headlines, photographs, hugs, a touchdown, too little or too much sleep, the sun, a poem, a cup of coffee, a lump of sugar, your commute, a nasty email, or a sip of wine all make their way into the brain, affecting the delicate brain chemistry–and more specifically, our neurotransmitters. The primary job of neurotransmitters such as serotonin, dopamine, and glutamate is to help the neurons in our body communicate with each other. The precise balance needed to function optimally is always being monitored. When there is a problem, like too little serotonin for too long, it can cause depression. Many antidepressants are designed specifically to boost serotonin in an effort to relieve the symptoms. However, these medicines can often come with unwanted side effects, such as low libido, weight gain, and in some cases (believe it or not) depression. This is one reason why some experts have estimated that the relapse rate for depression is as high as 80 percent. The good news is that there are other ways to improve the functioning of these and other neurotransmitters. These alternatives to antidepressants can reduce these same symptoms. Chief among these is exercise. In fact, according to the National Institute of Mental Health, it would be hard to beat exercise as one of the most effective (and natural) ways to alleviate this type of suffering. The question is: How does exercise affect the brain’s neurotransmitters? By engaging in moderate levels of exercise for 30 minutes, five times a week, and strength training twice a week, you can change the chemistry in your brain in ways that not only attack the biochemical issue at its core, but also reduce symptoms of depression naturally. Exercise does this through the production of a protein known as BDNF (brain-developed neurotropic factor), which helps brain neurotransmitters function better. Dr. John Ratey, Associate Clinical Professor of Psychiatry at Harvard Medical School, describes BDNF as “Miracle-Gro for the brain.” While exercise isn’t the only thing that can increase the expression of BDNF, it may be the more preferred. Antidepressants and electroconvulsive therapy (ECT) also increase BDNF–but often come with the side effects mentioned above for antidepressants, in addition to memory loss, in the case of ECT. In fact, exercise is so effective that it is now considered an evidence-based treatment by the American Psychiatric Association as both a stand-alone and an augmentation therapy for depression. This is worth repeating. Exercise can help improve the effectiveness of antidepressants or it may be able to do the job all on its own. Even moderate levels of exercise can be helpful because they enhance the effectiveness of neurotransmitters in your brain. If you haven’t taken a walk around the block or used that gym membership in a while, it may be time for a workout. There is a very good chance you will feel better afterward. Your brain will thank you for it.