By Meghan Pearson
But WHY Do I Run?
(As you can see, I always take it seriously…)
Running has always been a part of my life. I began by running around with my neighbors, then played soccer, then ran cross-country, and now, since I am a glutton for punishment, I run marathons. And before you ask, yes, I actually enjoy doing it. Luckily for me, recent science shows I am actually doing interesting things to my brain while I am running.
For the next month, Inner City Science and Faces of STEM will be reporting about exercise and science and the science of exercise. We are going to look at it from a lot of different perspectives, so stay tuned!
Exercise has long been known to have important health effects. We have all been told that it is an important part of life if we want to live long and prosper (ha!), but the why is a little harder to put into words. I am going to start with some basic studies that looked at what effect exercise had on the aging mind.
As we age, our bodies start to fail on us. It’s a slow process, but we have all probably seen or felt it. Maybe the metabolism slows, maybe the brain can’t remember things, or maybe there is the sudden urge to yell at kids to get off the lawn. The last one is a silly example, but you get the idea. Aging stinks. But research is actually starting to pour in that by exercising, we can slow (and sometimes reverse) some of the effects on aging.
Methods and Materials:
As stated above, there is much research in this topic; however, it should be noted as human testing is still very frowned on, most of these studies are done on mice and rats. Why is this still relative? Well, it turns out we are pretty similar to rats and mice (evolution is cool!)
Many scientists are interested in how to best preserve their brain power. In one such study, they began by comparing the learning abilities and new nerve cell growth of mice from four different groups: sedentary young mice, sedentary old mice, exercising young mice, and exercising old mice. They provided the third and fourth groups (the exercisers) with a wheel and monitored their use.
This is where it gets cool. They then compared how the mice performed on different a specific maze learning test, and it turns out, the mice that exercised did better! But it gets even better. While there was a difference in the performance between the young and old mice, the old mice performed outperformed their sedentary old mice peers, and in some regards, performed similarly to the young mice of the sedentary group. The mice were able to learn more effectively when they exercised. In fact, when the researchers looked at the brains of the mice, they found that the old mice that exercised had increased their neurogenesis. This is the scientific word for they were once again creating new dendrites: nerve cells! The old mice were not able to make as many new cells as their young peers, but the old mice that exercised showed more new growth than the sedentary old mice. They were reversing some of the effects of aging. It should also be noted that the old mice were all kept sedentary until they were 19 months old (remember, the life span of mice is only about two years…). These researchers believe that beginning to exercise sooner may have lessened the effects of aging even more.
So what does this mean for us? Well, it is pretty good motivation to get out the door and go exercise, but it also means that there are some pretty good indicators that exercising could help us feel young for longer. Human application of these studies is never perfect, but it is usually close. The sooner a person starts exercising, the sooner they can begin to have these benefits. So go outside, go to the park, chase your kids around. Give your brain a few extra dendrites so you can feel better for longer!
If you would like to read one of the papers about this topic, I encourage you to read Exercise Enhances Learning and Hippocampal Neurogensis in Aged Mice by Henriette van Praag et al.