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Stop Stress for Good: Exercise to Fight Stress

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The Best Stress Solution

Most mornings the alarm clock has barely gone off and Heather Allen, a 33-year-old vice president of a communications firm in Dallas, is already obsessing over the day's to-do list. Combining the demands of an all-consuming job with the challenges of being newly married and the things that come with that — a house, juggling budgets, and more — can seem overwhelming. "When I wake up, my brain is on fire," Heather says. "I'm thinking of a million conversations I need to have at work or in my personal life, maybe even one that I need to have again." Rather than take that pressure-cooker feeling to work, she lets it fuel her morning workout. "Exercise helps me regain my equilibrium," she says. "After a cardio class or hard workout, I don't even remember what I was stressing about."

A lot of us could use that relief. According to the American Psychological Association, a whopping 75 percent of people in the United States feel stressed out. Almost half of us eat unhealthy because of it; 47 percent of us can't sleep because of it; it makes one in three of us depressed; and for 42 percent of us, it has gotten worse in the last year. There is so much making us anxious these days — from big-picture problems like uncontrollable oil spills and a still-soft economy to garden-variety job, relationship, money, you-name-it woes — that it's easy to think of chronic stress as the new normal.

Unfortunately stress doesn't just mess with your head; it actually messes with your waistline. When you're faced with a nerve-racking situation, your body increases production of the hormone cortisol, part of what experts call the fight-or-flight response. If the stress-inducing situation disappears, your body returns to normal. If it remains? Well, that's the problem. The kind of stress most of us face is the ongoing sort — credit card bills, relationship tension, office layoffs — which keeps cortisol levels elevated for days. And that increased cortisol, in turn, appears to encourage the body to store additional abdominal fat.

An expanding belly is just one side effect of a stressed-out life. "Stress is associated with just about every chronic disease we know," says Jill Goldstein, PhD, director of research at the Connors Center for Women's Health and Gender Biology at Brigham and Women's Hospital in Boston. Heart disease, diabetes, depression, and some cancers are the most notable examples. Recent research from the Yale School of Medicine indicates that stress may also be responsible for encouraging addictive behaviors and other unhealthy habits by disrupting the part of your brain responsible for self-control and decision making.

Conventional wisdom suggests that you are just a deep breath, a relaxing bath, or a soothing movie away from discovering the secret to a stress-free life. But because the stress response is largely physical (your brain stimulates the release of certain powerful hormones that subsequently increase your blood pressure and heart rate), it's not always possible to think yourself calm, says Monika Fleshner, PhD, a professor in the department of integrative physiology at the University of Colorado at Boulder.

Rather, the latest research reveals that revving up your body with exercise may be the most effective antidote. In lab studies, when scientists at Princeton put animals on a six-week aerobic conditioning program, then compared their brain cells with those of a group that remained sedentary, they found that the "brains on exercise" morphed over time into a biochemically calm state that remained steady even when the subjects were under stress. The nonexercising group's brain cells continued to react strongly to anxiety-inducing situations. This breakthrough discovery has scientists now saying that cardio workouts may actually remodel the brain to make it more resistant to stress hormones.

The Power of Exercise

The power of exercise to protect against stress is encouraging news for women, who are more likely than men to experience certain harmful health side effects from feeling chronically maxed out, including a higher risk of depression and autoimmune diseases. Moreover, scientists at the Connors Center have discovered that anxiety-inducing situations can actually lead to different hormonal changes in women's brains than in men's.

Yet while they're more susceptible to stress on the one hand, women also appear to have a unique, built-in ability to alter their stress response. When scientists monitored the brain activity of a group of healthy men and women looking at disturbing images, women at the beginning of their menstrual cycle showed an emotional reaction similar to men's, but a lower stress response during ovulation. "Women are endowed with a natural hormonal capacity to regulate the stress response," says Goldstein, lead author of the study.

Tapping into that natural capacity, more and more research suggests, begins with regular exercise. When Pamela Epstein, a 25-year-old account manager at a public relations firm in New York City and self-described "perfectionist," ended a six-year relationship last fall while simultaneously starting a new job, she felt her stress levels soar sky-high and stay there. Suddenly living on her own for the first time, Pamela worried about making ends meet, carving out a new social life, and keeping up at work. She began seeing a therapist, who prescribed antianxiety meds but also insisted that Pamela start following a regular exercise regimen that would include at least an hour of cardio three times a week. "He said the medication might make me feel better but that, in the long run, keeping my body in the best physical shape possible would help protect me from stress in my life," Pamela says. "And he's right; after my workout, I always feel so much more relaxed."

In a study from Duke University Medical Center in Durham, North Carolina, doctors put patients who had been diagnosed as clinically depressed on an exercise regimen. After four months of consistently working out three times a week, researchers found a significant improvement in 45 percent of people who had been previously diagnosed with major depression.

"Exercise is like free medicine," says Robert Leahy, PhD, director of the American Institute for Cognitive Therapy and author of Beat the Blues Before They Beat You. "Medication may work more rapidly to lessen the symptoms of depression or stressed feelings, but the effects of regular exercise are longer lasting."

Rewire Your Brain

Part of the long-term relief is due to the unique way exercise helps build up a resistance to stress. "Through regular cardio, you actually change your brain, so it takes more and more stress to trigger the fight-or-flight response," says John Ratey, MD, an associate clinical professor of psychiatry at Harvard Medical School and author of Spark: The Revolutionary New Science of Exercise and the Brain.

It works like this: Cardiovascular activity helps the heart pump more blood to the brain. More blood means more oxygen; more oxygen leads to better-nourished brain cells. Recently scientists discovered that a vigorous workout causes brain cells to become more active and boosts the production of a protein called brain-derived neurotrophic factor (BDNF). "I call it Miracle-Gro for the brain," Dr. Ratey says. The protein's role, among other things, is to fortify brain cells to prevent them from breaking down when exposed to stress.

As we age, brain cells die off. Scientists used to think that the loss was permanent, that the brain couldn't make new cells to replace the dead ones. But a recent study from Denmark showed that exercise led to an increase in BDNF production.

With higher BDNF levels, we can preserve the brain cells we have and help make new ones."These new neurons will stick around for years," Dr. Ratey says. The catch? "If your body is sedentary, they shrink again. To maintain the effects, you have to keep working out." Of all types of activity, cardio workouts appear to give the biggest boost to BDNF production, according to recent studies. Other research shows that yoga and even strength training can be beneficial in producing chemicals that protect your brain from stress.

"Exercise helps produce resilience, not because it eliminates the stress response, which would be bad because you want your body to recognize and respond to dangerous situations, but because it acts as a buffer to it," the University of Colorado's Fleshner says. "Say your boss asks, 'Why haven't you met your deadline?' If you've been exercising regularly, you're less likely to respond with a full-blown physiological stress response — elevated heart rate, high blood pressure — as would someone who is sedentary." If you do get anxious, Fleshner says, your body's reaction is less exaggerated and the effects don't linger long enough to harm your health.

Perhaps the biggest perk for those who stick with a fitness program is that consistency is rewarded. In Fleshner's study, animals who were put on a regular exercise program for six weeks all showed a drop in anxiety levels because of changes in the stress response, including changes in the serotonin system. She believes the results would be similar for people. "More than anything, what we've realized is that the biochemical changes that occur to make us resilient to stress are cumulative," she says. "The more consistent you are with your workouts, the more you are rewarded with stress-fighting power." And that's reason enough to start lacing up now.

Easy Stress-Relieving Tips

Editors' Favorite Stress Busters

"I like to run long. Just go and go until all I can think about is right foot, left foot, right foot. I find the steady rhythm soothing."
— Julia Savacool, articles director

"I found a total-body conditioning class that I love. The instructor plays great '80s music and is super high energy. I always feel more relaxed afterward."
— Bethany Gumper, senior editor

"I take a walk with my dog. He's always excited to see me, and strolling through the park gives me a chance to decompress."
— Sara Wells, nutrition editor

Dodge This Stress Trap

Ever notice how your guy friends seem immune to situations that stress you out? Could be that you're overthinking things. "Women tend to ruminate," says Carolyn M. Mazure, PhD, professor of psychiatry and psychology at the Yale School of Medicine. "Our sense of blame tends to be more internal than external, while men typically attribute shortcomings to external factors." In other words, after a tough race, men might blame the crowded course or hot weather; women are more apt to chalk it up to their poor running skills. That constant self-criticism may be part of what makes women three times more likely to become depressed in response to a stressful event, according to a study in Psychological Medicine. Next time you catch yourself dissing your performance, stop and think about external variables that could be playing a role. It's not about dodging responsibility, but about being open to the fact that you don't live in a vacuum.

Originally published in FITNESS magazine, September 2010.