It’s well documented that exercise does a body good. It also works wonders on the brain, too. In the last several years, research has discovered that exercise promotes a process known as neurogenesis, which is the brain’s ability to grow new brain cells.
An excerpt in a October 2014 article in the Wall Street Journal provides the scientific explanation: “Research has discovered that exercise stimulates the production of a protein called FNDC5 that is released into the bloodstream while we’re breaking a sweat. Over time, FNDC5 stimulates the production of another protein in the brain called Brain Derived Neurotrophic Factor (BDNF), which in turns stimulates the growth of new nerves and synapses—the connection points between nerves—and also preserves the survival of existing brain cells.”
In other words, regular exercise actually fortifies, strengthens and grows your brain. The benefits of exercise are well-documented, and this is just another reason to get moving. But what form of exercise is best at increasing brain volume? A recent New York Times story detailing a groundbreaking study gives the answer.
Researchers at the University Jyvaskyla in Finland and other institutions compared the neurological impacts of running, weight-training and high-intensity interval training head-to-head. Using a large group of adult male rats, the researchers had one group of the animals with a spinning wheel in their cages, allowing them to run freely.
Another group began resistance training, which in this case involved rats climbing a wall with weights attached to their tails. Another group took part in high-intensity interval training (HIIT), which required rats to sprint at a strenuous pace for three minutes on treadmills, interspersed with two minutes at a jogging pace for a total of three sets and 15 minutes of run time.
The groups continued this for seven weeks, “after which the researchers microscopically examined brain tissue from the hippocampus of each animal. They found very different levels of neurogenesis, depending on how each animal had exercised.”
The rats that had jogged on spinning wheels “showed robust levels of neurogenesis. Their hippocampal tissue teemed with new neurons, far more than in the brains of the sedentary animals. The greater the distance that a runner had covered during the experiment, the more new cells its brain now contained.”
The running group had far more new neurons in their brains compared to the animals that completed the high-intensity interval training. The group of rats that did resistance-training showed no increase in neurogenesis, though they did get stronger. Of course, rats are not people, but the researchers’ findings are powerful.
Miriam Nokia, who led the study and is a research fellow at the University of Jyvaskyla, said in the story that “sustained aerobic exercise might be most beneficial for brain health also in humans.” The takeaway point from the research is distance running/endurance exercise of moderate intensity promoted greater neurogenesis.
Nokia also said that just because endurance running was the best form of exercise to strengthen the brain, it doesn’t mean you should stop resistance-training and HIIT. “Weight training and high-intensity intervals probably lead to different types of changes elsewhere in the brain. They might, for instance, encourage the creation of additional blood vessels or new connections between brain cells or between different parts of the brain.”
The takehome message? If you prefer resistance-training and HIIT, stick with it. But mix in a longer endurance cardio session to truly do your brain good.