Exercise and the Brain: The Many Benefits Draft

How cutting-edge research is showing the positive mental effects of moving the body.

Nearly every American can probably remember their doctor telling them to eat their vegetables and exercise, but for what reason? Most people think that these recommendations benefit the physical body. For instance, people lift weights to grow muscle or run miles burn the pizza they ate last night. However, in his groundbreaking 2013 book Spark: The Revolutionary New Science of Exercise and the Brain, Dr. John Ratey from Harvard Medical School explains that the true benefits of exercise are found within the brain. While there are physical benefits, these pale in comparison to the profound mental benefits exercise causes.

Learning and Motivation

Gym class at most schools are named physical education (PE) programs. Whether it is playing soccer or capture the flag, the basic goal behind these programs is to get children to move around. However, the paradox is being shifted towards fitness based PE programs, in which the focus of these programs is fitness exercise with an intention to improve brain function. In Naperville, Illinois, one such fitness based physical education program began in the early 1990s with the intent to stress fitness and the positive benefits of the brain receives from fitness. What exactly does “fitness based physical education” look like? The teachers use heart rate monitors to track the physical workload of students as they exercise aerobically, whether this be while students run miles and exercise on high-end Schwinn stationary bikes

An image of the typical heart rate tracker

Not only did the Naperville students become physically fit due to the high intensity workouts, but their tests scores increased along fitness level .As Ratey explains, “When the students in Titusville or in Naperville go for a mile run in gym, they are more prepared to learn in their other classes: their senses are heightened; their focus and mood are improved; they’re less fidgety and tense; and they feel more motivated and invigorated.” Furthermore, exercise literally creates new nerve cells from stem cells, thus literally creating new mental capacity.  The astonishing part is there is education data to backup this theory. The Naperville 203 school district scored number one in the world on the math and number six in the world on the TIMSS education test. For context, the average US school scored eighteenth in science and nineteenth in math relative to the world. “In addition to priming our state of mind, exercise influences learning directly, at the cellular level, improving the brain’s potential to log in and process new information.”

Regulating Emotions

Another non-physical, mental benefit from exercise is its ability to combat stress, anxiety, and depression. When people are stressed out, the brain gets locked into a pattern of stress. Over time, this pattern can be damaging and makes people feel like the stress will never end. However, moving the body can combat the stress. Exercise controls stress on a cellular level, thus leaving people feeling emotionally and physically because the cells repaired while the body moves. Due to the fight-or-flight phenomenon, in which human beings evolved to either fight or run during conflict, when people exercise when stressed, they actually are doing what humans evolved to do. This is a main reason why moving the body can help relieve stress.

Approximately 18% of the US population suffers from anxiety. In the brain, anxiety is when the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis increase activity. As doctor Ratey explains, “By using exercise to combat the symptoms of anxiety, you can treat the state, and as your level of fitness improves, you chip away at the trait. Over time, you teach your brain that the symptoms don’t always spell doom and that you can survive; you’re reprogramming the cognitive misinterpretation.” Overall, exercise while anxious provides a distraction, reduces muscle tension, builds brain resources, teaches different outcome, reroutes your circuits, and improves resilience.

With the emergence of function MRI and PET scans, scientists have been able to see what depression looks like in the brain. Essentially, depression is a change to the “emotional circuitry” of the brain and its messengers such as norepinephrine, dopamine, and serotonin. This leads to a breakdown at the cellular level, in which the brain is trapped in a negative cycle it cannot work its way out of. Dr. Ratey finds that exercise is as good if not better of a prescription for a person suffering from depression than modern drugs like Zoloft or Lexapro. Not only can exercise treat depression, but it is actually effective at preventing depression.

What Kind of Exercise Regime Is Best?

After reading about the numerous positive effects of exercise, you might wonder what types and for how long you should exercise. Unfortunately, it is not clear which type of exercise brings about the best mental benefits. As a rule of thumb, some exercise is better than nothing and more is better than less. “Research shows that the more fit you are, the more resilient your brain and the better it functions both cognitively and psychologically.” A variety of studies have shown that aerobic exercise can increase capillary volume in the memory area of the hippocampus, increase neurotransmitters and neurotrophic factors, and encourage neuroplasticity. There is essentially a positive relationship between mental and physical strength. So whether you run, cycle, or swim, you should mix up medium intensity workouts and high intensity workouts to gain the benefits of exercising different muscle groups.