Time to stop dust off the old running shoes – a 2016 study describes the specific benefits aerobic exercise, such as running, may have on stimulating growth of new brain cells! The study, published in the Journal of Physiology by a Finnish research group, reports that mice on certain exercise routines have more adult hippocampal cells, which are essential for learning, pattern separation, and other mental functions.
A growing body of research supports the idea that aerobic exercise can increase neurogenesis (the process of neuron growth). Studies from the last few years also indicate that this neurogenesis benefits not only the hippocampus, but also the hypothalamus, and other key zones of the brain.
This study compares traditional aerobic movements, like running, with alternative types of exercise in which many adult humans might participate. The researchers developed or adapted models of running, interval training, and weight training. In human physical training, each type of training has a specific purpose.
- Aerobic exercise has traditionally benefited the heart, muscles, and metabolism and has been considered a whole-body exercise. It is also considered a long-term solution, being low impact and low stress when done in moderation.
- Interval training, involving bouts of intense exercise with short breaks, increases blood-oxygen capacity, improves athletic performance and may be linked with the production of certain protective factors released in the blood and the brain. It has absolutely revolutionized certain racing sports; Ultra Short Race Pace Training has caused a remarkable change in competitive swimming and the same principles have been applied to high-level running, rowing, and biking.
- Finally, weight training is primarily recognized for increasing muscle mass, but animal studies suggest it may also increase spatial reasoning. The changes in strength are often viewed as in direct opposition to aerobic training and specifically running.
The caveat in all such exercise studies is that mild stress can be beneficial but prolonged, unpredictable, or excessive stress is almost always associated with degeneration, loss of neurogenesis and other systemic problems. It is the difference between a jogger and a marathon runner, a weight-lifter and a power-lifter, or a recreational athlete and a professional. All groups were compared to a ‘sedentary’ group of rats.
There is one morel eyebrow-raising fold in this study: they had two different groups of test subjects. Lab rats were bred for generations, pairing the animals which chose to run the most with each other, and separating the other animals who ran less. The researchers created one population who, genetically, liked running as well as another population who, genetically, typically chose not to run!
The study found, as expected, that rats who were predisposed to run had the most notable neurogenesis after running – the results were far less impressive for interval-training and sedentary groups. The mice who didn’t like running had a dampened response, but the neurogenesis in the running group was still impressive (better in fact than of any other group, run-loving or otherwise).
There are several take-away messages of this paper. First, aerobic exercise is more effective for neurogenesis than interval training, and weight training has almost no benefit. Second, there are definitely sub-populations in any group who respond better to exercise of all types; however, the benefit to either group is significant. So like it or not, running still helps. Finally, the amount of running is correlated to the degree of neurogenesis – so run more get smarter? Maybe not exactly, but at least so far as it has been tested, running is directly linked to certain neurogenesis.
While this study only studied adult males, previous work indicates it is likely true in females, older and younger animals, and quite likely humans. Several human retrospective studies confirm that activity often leads to improved cognitive function.
So, if you needed that extra push to go running as the weather warms, here you go: you’ll get better at crosswords, wittier at work, and you’ll remember your bank passwords (results may varying). This study does not detract from the real, physical benefits of interval training and strength training, but it does highlight the powerful role aerobic exercise has in regulating and maintaining these amazing bodies we have. Now, if only running for office could increase a person’s brain cells this country might be in luck!
Read the NY Times opinion by Gretchen Reynolds here!