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How exercise changes your brain biology and protects your mental health
Contrary to what some might think, the brain is a very plastic organ.
As with many other physicians, recommending physical activity to patients was just a doctor chore for me – until a few years ago. That was because I myself was not very active.
Over the years, as I picked up boxing and became more active, I got firsthand experience of positive impacts on my mind. I also started researching the effects of dance and movement therapies on trauma and anxiety in refugee children, and I learned a lot more about the neurobiology of exercise.
I am a psychiatrist and neuroscientist researching the neurobiology of anxiety and how our interventions change the brain. I have begun to think of prescribing exercise as telling patients to take their “exercise pills." Now knowing the importance of exercising, almost all my patients commit to some level of exercise, and I have seen how it benefits several areas of their life and livelihood.
We all have heard details on how exercise improves musculoskeletal, cardiovascular, metabolic and other aspects of health. What you may not know is how this happens within the brain.
How exercise improves the brain.
Brain biology and growth
Working out regularly really does change the brain biology, and it is not just "go walk and you will just feel better." Regular exercise, especially cardio, does change the brain. Contrary to what some may think, the brain is a very plastic organ. Not only are new neuronal connections formed every day, but also new cells are generated in important areas of the brain. One key area is the hippocampus, which is involved in learning and memory and regulating negative emotions.
A molecule called brain-derived neurotrophic factor helps the brain produce neurons, or brain cells. A variety of aerobic and high-intensity interval training exercises significantly increase BDNF levels. There is evidence from animal research that these changes are at epigenetic level, which means these behaviors affect how genes are expressed, leading to changes in the neuronal connections and function.
Moderate exercise also seems to have anti-inflammatory effects, regulating the immune system and excessive inflammation. This is important, given the new insight neuroscience is gaining into the potential role of inflammation in anxiety and depression.
Finally, there is evidence for the positive effects of exercise on the neurotransmitters – brain chemicals that send signals between neurons – dopamine and endorphins. Both of these are involved in positive mood and motivation.
Exercise improves clinical symptoms of anxiety and depression
Researchers also have examined the effects of exercise on measurable brain function and symptoms of depression and anxiety. Exercise improves memory function, cognitive performance and academic achievement. Studies also suggest regular exercise has a moderate effect on depressive symptoms even comparable to psychotherapy. For anxiety disorders, this effect is mild to moderate in reducing anxiety symptoms. In a study that I conducted with others among refugee children, we found a reduction in symptoms of anxiety and PTSD among children who attended eight to 12 weeks of dance and movement therapies.
Exercise could even potentially desensitize people to physical symptoms of anxiety. That is because of the similarity between bodily effects of exercise, specifically high-intensity exercise, and those of anxiety, including shortness of breath, heart palpitation and chest tightness. Also, by reducing baseline heart rate, exercise might lead to signaling of a calmer internal physical environment to the brain.
It is important to note that the majority of studies examined the effects of exercise in isolation and not in combination with other effective treatments of clinical anxiety and depression, such as psychotherapy and medication. For the same reason, I am not suggesting exercise as a replacement for necessary mental health care of depression or anxiety, but as part of it, and for prevention.
There are other perks besides the neurobiological impacts of exercise. When going out for a walk, one gets more exposure to sunlight, fresh air and nature. One of my patients befriended a neighbor during her regular walks, leading to regular taco Tuesdays with that new friend. I have made some great friends at my boxing gym, who are not only my motivators, but also a great supporting social network. One might pick a dog as their running mate, and another might meet a new date, or enjoy the high energy at the gym. Exercise can also function as a mindfulness practice and a respite from common daily stressors, and from our electronic devices and TV.
By increasing energy and fitness level, exercise can also improve self-image and self-esteem .
Practical ways for a busy life
So how can you find time to exercise, especially with all the additional time demands of the pandemic, and the limitations imposed by the pandemic such as limited access to the gyms?
- Pick something you can love. Not all of us have to run on a treadmill (I actually hate it). What works for one person might not work for another. Try a diverse group of activities and see which one you will like more: running, walking, dancing, biking, kayaking, boxing, weights, swimming. You can even rotate between some or make seasonal changes to avoid boredom. It does not even have to be called an exercise. Whatever ups your heartbeat, even dancing with the TV ads or playing with the kids.
- Use positive peer pressure to your advantage. I have created a group messaging for the boxing gym because at 5:30 p.m., after a busy day at the clinic, I might have trouble finding the motivation to go to the gym or do an online workout. It is easier when friends send a message they are going and motivate you. And even if you do not feel comfortable going to a gym during the pandemic, you can join an online workout together.
- Do not see it as all or none. It does not have to be a one-hour drive to and from the gym or biking trail for a one-hour workout vs. staying on the couch. I always say to my patients: "One more step is better than none, and three squats are better than no squats." When less motivated, or in the beginning, just be nice to yourself. Do as much as possible. Three minutes of dancing with your favorite music still counts.
- Merge it with other activities: 15 minutes of walking while on the phone with a friend, even around the house, is still being active.
- When hesitant or low on motivation, ask yourself: "When was the last time I regretted doing it?"
- Although it can help, exercise is not the ultimate weight loss strategy; diet is. One large brownie might be more calories than one hour of running. Don't give up on exercise if you are not losing weight. It is still providing all the benefits we discussed.
Even if you do not feel anxious or depressed, still take the exercise pills. Use them for protecting your brain.
- Why exercise might be better for mental health than meds - Big Think ›
- Exercise Shown to Alleviate Symptoms of Depression and Anxiety ... ›
The idea of 'absolute time' is an illusion. Physics and subjective experience reveal why.
- Since Einstein posited his theory of general relativity, we've understood that gravity has the power to warp space and time.
- This "time dilation" effect occurs even at small levels.
- Outside of physics, we experience distortions in how we perceive time — sometimes to a startling extent.
Physics without time<p>In his book "The Order of Time," Italian theoretical physicist Carlo Rovelli suggests that our perception of time — our sense that time is forever flowing forward — could be a highly subjective projection. After all, when you look at reality on the smallest scale (using equations of quantum gravity, at least), time vanishes.</p><p style="margin-left: 20px;">"If I observe the microscopic state of things," writes Rovelli, "then the difference between past and future vanishes … in the elementary grammar of things, there is no distinction between 'cause' and 'effect.'"</p><p>So, why do we perceive time as flowing <em>forward</em>? Rovelli notes that, although time disappears on extremely small scales, we still obviously perceive events occur sequentially in reality. In other words, we observe entropy: Order changing into disorder; an egg cracking and getting scrambled.</p><p>Rovelli says key aspects of time are described by the second law of thermodynamics, which states that heat always passes from hot to cold. This is a one-way street. For example, an ice cube melts into a hot cup of tea, never the reverse. Rovelli suggests a similar phenomenon might explain why we're only able to perceive the past and not the future.</p><p style="margin-left: 20px;">"Any time the future is definitely distinguishable from the past, there is something like heat involved," Rovelli wrote for the <a href="https://www.ft.com/content/ce6ef7b8-429a-11e8-93cf-67ac3a6482fd" target="_blank"><em>Financial Times</em></a>. "Thermodynamics traces the direction of time to something called the 'low entropy of the past', a still mysterious phenomenon on which discussions rage."</p>
The strange subjectivity of time<p>Time moves differently atop a mountain than it does on a beach. But you don't need to travel any distance at all to experience strange distortions in your perception of time. In moments of life-or-death fear, for example, your brain would release large amounts of adrenaline, which would speed up your internal clock, causing you to perceive the outside world as moving slowly.<br></p><p>Another common distortion occurs when we focus our attention in particular ways.</p><p style="margin-left: 20px;">"If you're thinking about how time is <em>currently</em> passing by, the biggest factor influencing your time perception is attention," Aaron Sackett, associate professor of marketing at the University of St. Thomas, told <em><a href="https://gizmodo.com/why-does-time-slow-down-and-speed-up-1840133782" target="_blank">Gizmodo</a></em>.<em> "</em>The more attention you give to the passage of time, the slower it tends to go. As you become distracted from time's passing—perhaps by something interesting happening nearby, or a good daydreaming session—you're more likely to lose track of time, giving you the feeling that it's slipping by more quickly than before. "Time flies when you're having fun," they say, but really, it's more like "time flies when you're thinking about other things." That's why time will also often fly by when you're definitely <em>not</em> having fun—like when you're having a heated argument or are terrified about an upcoming presentation."</p><p>One of the most mysterious ways people experience time-perception distortions is through psychedelic drugs. In an interview with <a href="https://www.theguardian.com/books/2018/apr/14/carlo-rovelli-exploding-commonsense-notions-order-of-time-interview" target="_blank"><em>The Guardian</em></a>, Rovelli described a time he experimented with LSD.</p><p style="margin-left: 20px;">"It was an extraordinarily strong experience that touched me also intellectually," he said. "Among the strange phenomena was the sense of time stopping. Things were happening in my mind but the clock was not going ahead; the flow of time was not passing any more. It was a total subversion of the structure of reality."<br></p><p>It seems few scientists or philosophers believe time is completely an illusion.</p><p style="margin-left: 20px;">"What we call <em>time</em> is a rich, stratified concept; it has many layers," Rovelli told <em><a href="https://physicstoday.scitation.org/do/10.1063/PT.6.4.20190219a/full/" target="_blank">Physics Today</a>.</em> "Some of time's layers apply only at limited scales within limited domains. This does not make them illusions."</p>What <em>is</em> an illusion is the idea that time flows at an absolute rate. The river of time might be flowing forever forward, but it moves at different speeds, between people, and even within your own mind.
The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
- Conflict and violence cost the world more than $14 trillion a year.
- That's the equivalent of $5 a day for every person on the planet.
- Research shows that peace brings prosperity, lower inflation and more jobs.
- Just a 2% reduction in conflict would free up as much money as the global aid budget.
- Report urges governments to improve peacefulness, especially amid COVID-19.
The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
- One especially mysterious thing about the asteroid impact, which killed the dinosaurs, is how it transformed Earth's tropical rainforests.
- A recent study analyzed ancient fossils collected in modern-day Colombia to determine how tropical rainforests changed after the bolide impact.
- The results highlight how nature is able to recover from cataclysmic events, though it may take millions of years.