By Dr. Mercola
Exercise is known to create new excitable neurons in the hippocampus, an area of the brain involved in thinking and emotions.
This would suggest that exercise might induce anxiety in physically active people, but, ironically, research shows that exercise is associated with reduced anxiety and calmness.
The reason for these seemingly incompatible exercise effects was recently explored by Princeton University, who appear to have revealed, as the New York Times put it, “an eye-opening demonstration of nature’s ingenuity.”1
Exercise Creates New Excitable Brain Cells… and Quiets Them When Necessary
Newly formed ‘young’ neurons can be prone to easy excitement, making them quite efficient at inducing anxiety. Physical exercise creates excitable new neurons in abundance, which is beneficial in the long run, but would be expected to increase anxiety rates in the short term.
However, a new animal study comparing running mice with sedentary mice found that while the exercising animals’ brains ‘teemed with many new, excitable neurons,’ they also contained new neurons designed to release a neurotransmitter called gamma-aminobutyric acid (GABA). GABA inhibits excessive neuronal firing.
This helps to induce a natural state of calm.2 Commonly prescribed anti-anxiety drugs like Ativan, Xanax and Valium actually exert a calming effect in this same manner, by boosting the action of GABA.
Exercise appears to go one step further, however, as when the mice were later exposed to a stressful situation, the study found that the exercising mice, as opposed to the sedentary mice, responded with only an initial rush of anxiety, followed by calm. What all of this suggests, one of the study’s authors noted:3
“ … is that the hippocampus of runners is vastly different from that of sedentary animals. Not only are there more excitatory neurons and more excitatory synapses, but the inhibitory neurons are more likely to become activated, presumably to dampen the excitatory neurons, in response to stress.
… I think it’s not a huge stretch to suggest that the hippocampi of active people might be less susceptible to certain undesirable aspects of stress than those of sedentary people.”
Exercise Can Be a Key Anti-Anxiety Treatment
Some psychologists swear by exercise as a primary form of treatment for depression, anxiety and other mood disorders. Research has shown again and again that patients who follow regular exercise regimens see improvement in their mood -- improvements comparable to that of those treated with medication.
The results really are impressive when you consider that exercise is virtually free and can provide you with numerous other health benefits too. The benefits to your mood occur whether the exercise is voluntary or forced, so even if you feel you have to exercise, say for health reasons, there’s a good chance you’ll still benefit.
For instance, researchers at the University of Colorado Boulder devised an animal study to determine whether rats that were forced to exercise would experience the same stress and anxiety reduction as those who were free to choose if and when to exercise.4
The rats exercised either voluntarily or forcibly for six weeks, after which they were exposed to a stressor. The following day, their anxiety levels were tested by measuring how long they froze when placed in an environment they’d been conditioned to fear. The longer the rats remained frozen, like “a deer in headlights,” the greater the residual anxiety from the previous day’s stressor. According to the lead author:5
"Regardless of whether the rats chose to run or were forced to run they were protected against stress and anxiety. The sedentary rats froze for longer periods of time than any of the active rats. The implications are that humans who perceive exercise as being forced — perhaps including those who feel like they have to exercise for health reasons — are maybe still going to get the benefits in terms of reducing anxiety and depression."
What Type of Exercise Is Best for Anxiety?
If you struggle with anxiety, you really can’t go wrong with starting a comprehensive exercise program – virtually any physical activity is likely to have positive effects, especially if it’s challenging enough. That said, Duke University researchers recently published a review of more than 100 studies that found yoga appears to be particularly beneficial for mental health.6 Lead author Dr. P. Murali Doraiswamy, a professor of psychiatry and medicine at Duke University Medical Center told Time Magazine:7
“Most individuals already know that yoga produces some kind of a calming effect. Individually, people feel better after doing the physical exercise. Mentally, people feel calmer, sharper, maybe more content. We thought it’s time to see if we could pull all [the literature] together… to see if there’s enough evidence that the benefits individual people notice can be used to help people with mental illness.”
According to their findings, yoga appears to have a positive effect on:
- Mild depression
- Sleep problems
- Schizophrenia (among patients using medication)
- ADHD (among patients using medication)
Some of the studies in the review suggested yoga can have a similar effect to antidepressants and psychotherapy, by influencing neurotransmitters and boosting serotonin. Separate research also found that three months of regular yoga sessions resulted in less anxiety and depression, with anxiety scores falling from an average of 34 (on a scale of 20-80) to an average of 25.
However, while recent studies support the use of yoga to improve common psychiatric disorders (along with providing many other health benefits, such as promoting flexibility and core muscles, alleviating back pain, and more), I think it’s important to incorporate a variety of exercises into your routine for optimal health results. Ideally, you’ll want a comprehensive fitness program that high-intensity interval training like Peak Fitness and resistance training as well, in addition to flexibility and core-building exercises like yoga or Foundation Training.
The Mood-Boosting Benefits of Exercise Are Both Immediate and Long-Term
Rather than viewing exercise as a medical tool to lose weight, prevent disease, and live longer – all benefits that occur in the future – try viewing exercise as a daily tool to immediately enhance your frame of mind, reduce stress and feel happier. One study found, for instance, that while many people started an exercise program to lose weight and improve their appearance, they continued to exercise because of the benefits to their well-being.8
In addition to the creation of new neurons, including those that release the calming neurotransmitter GABA, exercise boosts levels of potent brain chemicals like serotonin, dopamine, and norepinephrine, which may help buffer some of the effects of stress. Many avid exercisers also feel a sense of euphoria after a workout, sometimes known as the “runner’s high.” It can be quite addictive, in a good way, once you experience just how good it feels to get your heart rate up and your body moving.
Best of all, these mood-boosting benefits are both immediate and long-term. The featured study found that the exercising mice still responded with increased calm even when they hadn’t exercised for 24 hours.
“The runners’ wheels had been locked for 24 hours before their [stress-inducing] cold bath, so they would gain no acute calming effect from exercise. Instead, the difference in stress response between the runners and the sedentary animals reflected fundamental remodeling of their brains,” the New York Times reported.9
What does this mean for you? Adding a regular exercise program to your life is likely to make you feel good each time you exercise plus enhance your mood, lessen anxiety and induce more feelings of calm in the future, too.