Fernando Gomez-Pinilla, a professor in the departments of Neurosurgery and Integrative Biology and Physiology at University of California Los Angeles, tells Inverse exercise is important for both physical and mental health. Staying active works synergistically with other healthy habits, like clean eating and getting enough sleep, to keep our minds sharp and ready to take on the world.
Essentially, to keep your brain healthy, you have got to move.
Here are five of the key benefits exercise can have on the brain:
Physical exercise trains your brain
Together with a team of researchers, Gomez-Pinilla published a 2017 review of 17 peer-reviewed studies, ultimately concluding exercise is good for your brain in the short term, but it also has a greater, longer lasting affect, too.
Exercise changes the brain on an epigenetic level — altering patterns of chemical tags on the body's DNA which influence gene expression. These changes can be permanent, and in some cases, may even be passed on to the next generation.
Exercise appears to regulate epigenetic changes in the hippocampus — a major learning and memory center in the brain, the review found. It also increases the production of certain molecules associated with enhanced learning and memory, according to the paper.
“The brain of people who exercise is more prepared for… learning,” Gomez-Pinilla says.
Whether exercise-related epigenetic changes can be inherited in humans is still an open question, Gomez-Pinilla says. But experiments in animal models and epidemiological studies suggest there may be epigenetic trends passed down within families.
If so, the implications are far-reaching. As Gomez-Pinilla and his co-authors conclude in the review:
"The understanding of how exercise promotes long-term cognitive effects is crucial for directing the power of exercise to reduce the burden of neurological and psychiatric disorders."
Aerobic exercise staves off cognitive decline
As early as your 30s, your brain shows signs of deterioration — the wear and tear that comes with age. The wear is particularly dramatic in the brain's frontal, parietal, and temporal lobes. And deterioration comes with a measurable decline in cognitive processes as well.
Enter exercise to save the day.
In a randomized clinical study published in 2006, researchers found doing 3 sessions of aerobic exercise lasting one hour for 6 months increased brain volume in previously sedentary older adults aged between 60 and 79 years old. Curiously, a second group of older adults who followed a toning and stretching regime did not experience similar benefits.
Doing cardio regularly could spare the brain from the ill-effects of aging, the study authors conclude.
Regular activity boosts attention, memory and comprehension
The brains of young people also benefit from exercise.
In a study published in 2019 in the journal Neurology, researchers compared the effects of doing aerobic exercise four times a week for six months versus a similar toning and stretching regimen in adults between the ages of 20-67.
The participants were evaluated for cognitive function, body mass index, aerobic capacity, and cortical thickness before and after taking part in the exercise intervention.
In the aerobic regimen group, they found some predictable results — BMI decreased and aerobic capacity increased. But they also found increases in cognitive function. Cortical thickness also increased significantly. None of these effects were found in the toning and stretching group.
While the study found that the positive effects on cognitive function were more pronounced in older participants, the study authors emphasize that “increased cortical thickness suggests that aerobic exercise contributes to brain health in individuals as young as age 20.”
Exercise strengthens stress resilience
Staying active is important for reducing stress, and for increasing your ability to cope with stressful events when they do occur.
In a 2020 study published in the Journal of Neuroscience, researchers studied galanin production in physically active mice. Galanin is a protein that is responsible for information transmission in the brain and galanin dysregulation may play a role in several mental health disorders in humans.
The researchers investigated mouse galanin using two different strategies — one in which mice voluntarily ran on a wheel, producing galanin naturally, and another in which mice were genetically modified to produce abundant galanin.
In both cases, mice with increased galanin also showed higher resiliency to stress. The researchers note exercise is often a helpful treatment for mental health conditions even when pharmacological options fail. Ultimately, the study results “support a role for chronically increased…galanin in mediating resilience to stress.”
Exercise safeguards against depression
“A lack of exercise, certainly, is directly connected to depression and several mental disorders,” Gomez-Pinilla says.
Conversely, exercise may work as a treatment for depression.
In one study, adults in their early twenties who suffered from major depression were randomly assigned a regimen of either light stretching or moderate-intensity aerobic exercise. Depressive symptoms were evaluated throughout the 8-week study.
Aerobic exercise reduced symptoms more effectively than stretching, according to the analysis. Interestingly, the more pronounced an individual's symptoms were, the more effective the aerobic activity was in combating these effects, the study found.
The inverse analysis — Despite the clear benefits of exercise on our mental health, we as a society are becoming more sedentary. The Covid-19 pandemic has only exacerbated the situation. It is possible we’re "going to see the effects [of the pandemic] in the next few years," play out in terms of the rates of mental health and brain conditions, Gomez-Pinilla says.
Even if you can’t go running every day, you should be as active as you can, Gomez-Pinilla says. This is in line with recently updated exercise recommendations from the World Health Organisation — any movement is better than none.
“Small things… can make a big difference,” Gomez-Pinilla says.