In 2000, Arvid Carlsson won a Nobel Prize for his 1958 work (with Nils-Ake Hillarp) at the Laboratory for Chemical Pharmacology of the National Heart Institute of Sweden that showed dopamine's powerful role as a neurotransmitter.
"It's important to understand that there is a biological component to motivation," says Lardon.
Your body changes physiologically when you are inspired. When a child hits a home run in a Little League game and you watch her run around the bases, dopamine is released in your brain. When you fall in love, dopamine is released. Once you've been rewarded with dopamine a few times, you've engaged the dopamine reward pathway. It doesn't take much to motivate you to repeat those experiences. In fact, research has found that the dopamine sensation is so pleasurable that you may become driven to experience it again. Experiments with rats that can choose either cocaine or food have demonstrated that rats will consistently choose the cocaine until they've starved to death. That's a staggering amount of motivation.
The neurobiological rewards of exercise are in fact twofold. The first are the natural endorphins - natural opiates - that are activated by your body when you exercise. As a result, you experience the much touted "runner's high." The second reward system that resides within your body is far more significant than endorphins, and that is dopamine.
The feel-good response of the dopamine reward pathway is much more all-encompassing and powerful, but it's also much more accessible. If you only use a treadmill (or do any exercise) for 20 minutes at a time, you will probably never reach the runner's high because the endorphin system takes longer than 20 minutes to kick in. But you definitely engage the dopamine reward pathway.
Dopamine is released within just 20 minutes of moderate exercise, Lardon says, and triggers within your brain positive feelings about yourself even after your first session of exercise, before your body has had a chance to firmly establish an association between the exercise and the great feelings. The dopamine response system is powerfully motivating.
Once you engage the dopamine reward pathway, your body becomes unconsciously driven - just like those mice - to experience more. The dopamine pathway has been shown to provide a level of motivation that can overcome almost any level of inertia. Have you ever seen someone out for a jog in driving rain, in the dark? What you are very likely seeing is the potent dopamine reward pathway in action.
Once you have exercised and engaged the pathway just a few times, the reward pathway will be firmly established. For the most part, your brain will unconsciously link exercise and the exhilarating rewards of dopamine, and that association will be reinforced every time you exercise and experience the exhilaration again. Soon you look forward to any opportunity to exercise. Like so many athletes have discovered: Exercise itself becomes a reward.
If you're not already enamored of exercise and would like to be, while you're still feeling motivated from watching the Olympians in action, give it a try. Think about the words of Wayne Gretzky, the great Canadian athlete who lit the outdoor cauldron to officially launch the Vancouver Olympics: "You miss 100 percent of the shots you never take."
( Eric Heiden, M.D., a five-time Olympic gold medalist speed skater, is now an orthopedic surgeon in Utah. He co-authored "Faster, Better, Stronger: Your Fitness Bible" (HarperCollins) with exercise performance physician Max Testa, M.D., and DeAnne Musolf. www.fasterbetterstronger.com)