Your Brain on Exercise


We all know exercise is great for your health: it burns calories, it helps you lose weight, and it keeps you busy. There is little to lose and much to gain by exercising regularly, but it gets even better. Exercise has been found to have an additional health benefit in mice: it affects the number of neuronal stem cells, as well as promoting the growth and resilience of progenitor cells in the dentate gyrus of mice.

You may be thinking: why should I care about a mouse’s brain? Believe it or not, the anatomy, physiology, and metabolism of mice are actually fairly similar to humans in key aspects. Effects and tendencies of a mouse’s brain closely reflect those of a human, so much so that trends researchers may find in mice can usually be extended to apply to humans. Furthermore, mice can be used for a wider range experiments than humans, allowing researchers to learn vital information about humans that would otherwise be impossible to find out.

Additionally, you might wonder what a progenitor cell is and why the dentate gyrus so important. A progenitor cell is similar to a stem cell in that it is not destined to be any one kind of cell, but it has a narrower range of cells it can become. The dentate gyrus is a part of the hippocampus and plays a role in both the creation of new memories and in decreasing the symptoms of depression. Thus, increasing the number of cells in the dentate gyrus can aid your memory abilities and your ability to deal with stress and depression.

So, what exactly is the relationship between exercise and neurogenesis? According to a study by Chih-Wei Wu et al., exercise increases the number of stem cells throughout the brain and the number of progenitor cells in the dentate gyrus. Normally, the number of neuronal stem cells rapidly declines by the time the mouse reaches middle age, whose total lifespan is around two years. As such, the researchers implemented a rigorous exercise plan — running on a treadmill — for two age groups of mice: at 8 months old and at 12 months old. Upon completing five weeks of the exercise regiment, the brains of the mice were studied.

For both age groups, the researchers saw that the number of stem cells and progenitor cells had significantly increased in both conditions compared to mice who did not exercise. However, the effect was much stronger in the younger age group, which took place before the decline normally occurs. In fact, the younger group had approximately twice as many cells than the control group.

What does this mean for you? Well, it means that exercise is likely to increase the number of cells in your dentate gyrus, which could increase your ability to make new memories and deal with stress. For you readers who are still young, exercise will greatly increase your mental health! And for all you readers who are seasoned in life, you still benefit from exercise! So the next time you find yourself with time to spare, please consider going on a walk or doing some physical exercise you enjoy: your brain will thank you!

By: Travis Talcott