Everybody knows that endurance/aerobic activity improves cognitive function by increasing blood flow to the brain. But what about resistance training? Most of the research on exercise and brain function to date has focused on low-intensity aerobics, such as long distance running and cycling. But in two exciting new studies, featured in a recent article in the New York Times, researchers found that weightlifting creates new brain cells–neurogenesis.
Perhaps one of the reasons for the dearth of research on strength training and brain function is the challenge presented in getting rodents to lift weights. But creative researchers from Brazil found a way to attach weights to the rodent’s tails and then they had them climb a ladder five days a week, while another group ran on a treadmill and a third group did nothing.
At the end of eight weeks the researchers found that both the resistance and aerobic exercise groups had an increase in brain-derived neurotropic factor (BDNF), a growth factor involved in neurogenesis, which was measured by how well the rats negotiated a water maze — a test of learning and memory. The sedentary group showed no improvement.
In another study, researchers from Japan looked at voluntary wheel running in rodents, similar to what the Brazilian researchers studied, but in this case they added a load to the wheel, changing the activity from low-intensity aerobic to high-intensity strength and power.
At the end of four weeks the researchers found that the loaded wheel running group had gained muscle and showed significant increases in levels of gene activity and BDNF in their brains. They also found that the higher the workload, or intensity, the greater the genetic activity within their brains. Min-Chul Lee, a researcher at the University of Tsukuba in Japan and lead author of the study said these findings indicate that “this kind of exercise may have the identical or even more useful effects than endurance training (e.g., treadmill exercise) on the rat brain.”
While the mechanisms involved in improving cognitive function are unclear, Teresa Liu-Ambrose, a principal investigator at the Brain Research Center at the University of British Columbia, speculates that increased blood flow to the brain and the learning involved in proper form and technique may be responsible for the improvements.
The idea that lifting heavy weights improves brain function makes perfect sense because heavy weights demand strong focus, especially if you are performing functional (foot-based) full-body movements. Snatching a heavy kettlebell, for example, requires maximal mind-body awareness to execute with good form. Even further, lifting heavy things is something we as a species have evolved to do as early ancestors adapted to the environment. These researchers are just tapping into an evolutionary adaptation. When we imitate the movement patterns of ancestral humans, we always benefit.