Better Fitness, Better Brain?
Exercise has many benefits, including keeping muscles strong and in shape, but studies also indicate that exercise can play a role in keeping our brains in shape. For example, research on “neurogenesis,” or the ability of certain brain areas to grow new brain cells, points towards exercise encouraging new brain cell growth.
In fact, the area in the brain called the hippocampus, which is closely linked to learning and memory, is particularly open to new neuron growth from endurance exercise. Here’s why: Exercise stimulates the production of a protein called FNDC5 that is released into the bloodstream as we exercise. As time goes on, FNDC5, in turn, stimulates the protein in the brain called Brain Derived Neurotrophic Factor, or BDNF, which then stimulates the growth of new nerves and synapses—the connection points between nerves—and helps to preserve existing brain cells.
What this means is that regular endurance exercise such as jogging can strengthen and grow the brain. If jogging’s not your thing, then regular brisk walking can deliver brain benefits.
Additionally, a study published in Medicine & Science in Sports & Exercise found that only three years of exercising influenced brain size; more specifically, it enlarged the areas of the brain known as the striatum and pre-frontal cortex. The striatum is a component of the basal ganglia, a group of nuclei that have many functions, but are big players in facilitating smooth, fluid voluntary movement. Located at the front of the frontal lobe in the brain, the pre-frontal cortex plays a role in complex behaviors, including planning and personality development.
So, why does keeping the brain larger matter? Brain shrinkage can be a sign of brain aging or even dementia, and not exercising over time can lead to brain shrinkage. In fact, research out of Boston University School of Medicine in Massachusetts showed a connection between levels of fitness in middle age—an average age of 40—and brain volumes later in life. Their findings, published in Neurology, showed that those who had poorer physical fitness had smaller brains 20 years later. The research team found that for every eight-unit decrease in exercise performance, brain volumes dropped in size equivalent to two years of additional aging.
Nicole Spartano carried out the research, using data from the Framingham Heart Study. She observes, “We found a direct correlation in our study between poor fitness and brain volume decades later, which indicates accelerated brain aging.” She adds, “From other studies, we know that exercise training programs that improve fitness may increase blood flow and oxygen delivery to the brain and improve neuroplasticity over the short term. Over the course of a lifetime, these mechanisms may have an impact on brain aging and prevent cognitive decline in older age.”
Since the average age for participants in this study was 40 when they were first tested and an average age of 60 when tested later, what does that mean for those who are older who want to keep their brains healthy through exercise? Is it too late for them? Probably not. Here’s why.
In a small study, with 60-year-olds to 79-year-olds who participated in six months of aerobic exercise, both white matter and grey matter in the brain increased in volume. To further clarify, the brain is divided into two parts: white matter and grey matter. White matter fills 60 percent of the brain, while grey matter makes up 40 percent of the brain. So, in short, the entire brain increased in volume.
Another study’s findings pointed out that a 12-week fitness program for 57-year-olds to 75-year-olds improved resting cerebral blood flow and performance in memory tasks.
All said, that means that we may be able to chalk up yet another benefit to exercise and better fitness—a better brain.
This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.