You must be one of those "Gym people." All that jogging! Stop running away from your problems. You do triathlons, eh? Get a life!
If you're dedicated to sports and fitness, you've probably heard these sentiments from unenlightened, conceivably envious and possibly even deconditioned people who believe that there are far more important things to do than working out. These 100-pound-weakling types ( from the old Charles Atlas ads in which built-up bullies kicked sand in the faces of scrawny nerds and walked away with the gals) speak in lofty tones about "improving your mind"- as if brain and brawn were mutually exclusive, and you had to choose between being Arnold Schwarzenegger and Stephen Hawking.
Well, now you can silence those critics. A growing body of scientific evidence has established that lifting weights builds not only your biceps, but also your brain. That's right: what seems like mindless Exer-cycling to those gym-aphobes is actually making you smarter-more confident and capable and better able to fight off the effects of aging.
Making the Exercise-Cognition Connection
The most recent study to verify the exercise-cognition connection, the results of which were publihsed in the November 2006 issue of the Journal of Gerontology revealed that subjects who exercised for six months showed an increase in the amount of specific kinds of brain tissue. Kirk Erickson, Ph.D., a scientist at the Beckman Institute for Advanced Science and Technology of the University of Illinois and one of the researchers who conducted the study, had one group of subjects walk three days a week for 45 minutes, while the control group were given non-aerobic stretching exercises. After six months, brain scans revealed that the aerobic group had experienced a 2 percent growth in the prefrontal lobe, the site of higher-level functions such as goal-planning and multi-tasking.
This enlargement occurred as a result of the production and release of chemicals in the brain triggered by exercise. The most important of these chemicals is brain-derived neurotrophic factor (BDNF), which contributes to the cellular components of memory and the production of new neurons in the hippocampus (a site in the brain that regulates emotion and learning.)
BDNF also helps build new veins, capillaries and arteries in the brain, and this increased blood flow allows neurons to function more effectively, which in turn makes them larger and stronger. Rats with boosted BDNF levels navigate mazes and recover from brain injuries faster than those with lower levels. Research even has suggested that an increase in BDNF helps rats avoid rodent depression (or, at least, the behavior that may reflect it, such as-I'm guessing here-lying in the corner of the cage sucking on the sugar drip instead of navigating the maze).
In essence, BDNF rewires the brain.
While these effects have been proven only in rats, Erickson says, "Since the molecular structure of BDNF is the same as in rats, monkeys and humans, we have a number of reasons to think that the chemical works the same way in people."
Exercise also has been shown to have a positive effect on troublesome brain disorders such as attention deficit hyperactivity disorder (ADHD), a neurological/behavioral condition resulting in hyperactivity and the inability to focus on tasks.
Some preliminary animal research even suggests that exercise can cause new stem cells to grow via BDNF, refreshing the brain and other body parts.
Conteracting the Effects of AgingThe brain-building fruits of exercise are tremendously important, especially for older people. That's because aging damages the brain; in fact, we start to lose brain tissue as early as our third decade.
However, people who exercise will lose brain tissue more slowly. A 2003 study at the University of Illinois at Urbana-Champaign, led by psychology and neuroscience professor Arthur F. Kramer, Ph.D., revealed that six months of regular aerobic exercise altered the middle frontal and superior parietal regions of the brain in aging adults, improving their ability to to concentrate. Kramer used magnetic resonance imaging (MRI) tests to measure brain activity in adults ages 58 to 78, and the results demonstrated that athletic older adults had denser brains than their inactive counterparts, suggesting that the workouts, in effect, protected their brains.
Therefore, it's no surprise that, according to Erickson, BDNF-or lack therof-plays a role in Alzheimer's and Parkinson's disease, both of which are largely age-related.
Erickson says that the next goal of this research group is to see "if the exercise-induced brain growth leads to improvements in human cognition." There is some reason for optimism: In a recent review of 18 studies, inactive older adults who began an exercise routine got progressively and significantly better at cognitive tests that measured skills such as planning and paying attention.
In addition to its direct effects on brain size and strength, exercise also boosts levels of serotonin and dopamine. These "mood" chemicals provide vitality, alertness and feeling of tranquility and euphoria, and stave off depression.
Carla Sottovia, assistant fitness director and senoir personal trainer at the Cooper Aerobics Center in Dallas, says that after exercise, people have both a higher concentration of brain cells and an increase in epinephrine, another mood hormone.
People who are less depressed and in a better mood are more productive and creative people, says Jim Taylor, Ph.D., a sports psychology consultant. "Exercise gives people tremendous motivation and belief in one's capabilities," he says, "And a large part of what we call intelligence is awareness that you have certain tools and the confidence to use them. For example, if a person believes that he's deteriorating from old age, he's not going to use his gifts, whether or not he's physiologically declining."
In other words, perception becomes reality, and participation in fitness and sports encourages people to perceive themselves as vital and not decrepit.
Taylor adds that sports build cognitive function because they require focus, decision-making and emotional control.
So, how much exercise do you need to do? Find out in: