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By way of example, Sternberg tells the story of a U.S. Navy pilot she once met who routinely flew F-14 fighter jets from aircraft carriers. The pilot admitted that when he flew under duress—say, while taking off or landing his craft on a carrier in the middle of the night during a rainstorm in the Sea of Japan—he felt all those things most of us feel when we're stressed. His heart raced and his palms sweated. But he was not completely stressed out, because he felt in control and able to use the mechanisms of the stress response to his advantage.

When you can't control your situation, says Sternberg, another strategy is to try to quiet your mind through deep breathing and meditation. Richard Davidson of the University of Wisconsin and his colleagues recently explored the physiological changes underlying so-called mindfulness meditation. In this technique, the meditator focuses on the moment, on the quiet awareness of breathing, allowing feelings and thoughts to wash over the mind without judgment or action. Studies have shown that mindfulness meditation can be a powerful antidote to anxiety disorders, chronic pain, and hypertension; one study even demonstrated that it had a significant effect on the rate that skin cleared up in patients with psoriasis.

Davidson's team studied forty-one employees of a biotechnology company. Twenty-five of the participants underwent an eight-week meditation program. When the scientists measured brain electrical activity before and after the eight-week session (and again four months later), they found that meditators showed more electrical activity than nonmeditators in the brain's left prefrontal cortex, a region previously shown to be associated with generally positive emotions—enthusiasm, optimism, confidence. Moreover, the team uncovered a direct link between this positive mental activity and health, specifically the robustness of the immune system. Meditators who demonstrated the boost in left prefrontal cortex activity also showed the most vigorous response to a flu vaccine; months after the experiment, they produced the highest levels of flu-fighting antibodies. The magnitude of the increase in left-brain activity predicted the magnitude of the antibody response to the vaccine—the greater the left-sided activation, the more antibodies produced.

Another remedy for nervous emotion is music. A short time after 9/11, in a church on a tree-lined street in my hometown, a chorus of hundreds gathered to sing Mozart's Requiem Mass in D Minor. The church was designed for a congregation of three hundred, but that day the crowd spilled over into the aisles and the vestibule and out the two massive front doors. Most of us were there because we sought comfort but could not bear the somber speeches, vigils, and formal ceremonies commemorating those lost in the attacks. Hearing neighbors and friends perform Mozart's final and unfinished masterpiece seemed a fit way to pay tribute to so many unfinished lives.

The mass for the dead began. I grasped only a little of the Latin
—requiem,
of course, and
recordare
and
lacrymosa—
so I listened instead for the pure, brilliant strains of music in which the smallest changes were meaningful, creating order, melody, and harmony out of chaos.

In
The Magic Mountain,
Thomas Mann's character calls music a "politically suspect" art because of the way it can move people by appealing directly to their emotions, swaying their moods, even inciting them to action against their better judgment. But by the same token, music has the power to remind, soothe, heal—which it did that day, in spades. Think of the way that music consoles at weddings, marches, funerals. Think of how some pieces send chills up the spine—the last movement of Beethoven's Symphony no. 5, for instance, or Samuel Barber's Adagio for Strings. Music with a quick tempo in a major key has been shown to produce in listeners many of the physical changes associated with joy: excitement, rapid heartbeat, release of endorphins, goose bumps. Music of slow tempo in a minor key elicits changes linked with sadness, an experience of "negative" emotion that, oddly enough, is considered rewarding by most people and sought after as pleasurable and comforting.

Not long ago, scientists at the Montreal Neurological Institute asked a group of musicians to choose music that evoked such powerful responses, and then took
PET
scans of their brains as they listened to their choices. The scans recorded intense activity along the neural pathways in the brain associated with keen pleasure and reward—the same pathways activated by eating, sex, and drugs. Other studies suggest that music can lower blood pressure and trigger the production of endorphins, those natural opiates released by the body in response to pain or stress.

It's interesting to note that other species share our susceptibility to soothing music. Dairy cows make more milk when listening to a classical piece such as Beethoven's
Pastoral
Symphony or a popular song like "Moon River" than when exposed to the rapid beat of Supergrass's "Pumping on Your Stereo" or Wonder Stuffs "Size of a Cow." The slower, more calming music appeared to reduce stress and relax the Holsteins, increasing their milk yield by a pint and a half per cow per day. I wish I'd thought to pump out some Puccini that afternoon to pacify our renegade bull before he stressed out the whole neighborhood.

Perhaps the oldest of all stress remedies are two I've always believed were best at undoing the damage of a day: humor and companionship. Now science is confirming my suspicions. People with strong social networks fare better in coping with stress, especially with respect to heart disease, immunity, and brain function, says Bruce McEwen. "Social support is a powerful talisman" against stressful pressures.

So is a good laugh. Allan Reiss and his colleagues at Stanford University used neuroimaging to peep inside the heads of volunteers and watch which brain regions grew active when they exposed the subjects to a series of forty-two cartoons deemed side-splitting by a cohort of similar age and background. The neuroimaging revealed that the comics roused not just the modern, thinking cortex used to analyze the jokes, but also the brain's ancient reward circuits, the mesolimbic regions—those same dopamine-rich areas triggered by alcohol and mind-altering drugs.

That humor sparks the brain's primeval salience and reward system suggests that laughter has been around for longer than we have and may have survival value. E. B. White once wrote, "Humor can be dissected, as a frog can, but the thing dies in the process and the innards are discouraging to any but the pure scientific mind." Teasing apart the neural roots of a good guffaw may seem an ideal way to unweave the rainbow. But I like knowing that laughter is stress therapy rooted in ancient neural threads of joy.

What most powerfully affects the stress equation, in McEwen's view, are the personal choices we make on a daily basis. For most of us, "the real problem is our modern lifestyle," he says, our habit of working too long and too hard, depriving ourselves of sleep, eating too much high-fat food, all of which feeds directly into our stress load and perturbs our normal stress response.

How to nudge the body in the right direction? Mellow out with friends, meditation, or music. Laugh. Most important, McEwen says, eat well, get enough rest, lay off the fatty foods and cigarettes, and, especially, get out and exercise—a great excuse to leave work a little early and hit the gym.

8. IN MOTION

"T
ASTE YOUR LEGS, SIR;
put them to motion," cries Sir Toby Belch in
Twelfth Night.
Doing so will significantly reduce your anxiety, clear your head, even relieve depression. I try to jog after work a few times a week on the hilly streets of Charlottesville, which I prefer to any running track. (On a track or treadmill I feel as Robin Williams does, like a hamster.) The run keeps me in shape, but more important, it's the best cure I know for my own stress and malaise.

The word has been out for decades about "runner's high," but there wasn't much science to support the claim that exercise affects mood. That has changed of late. More than a hundred studies have found that aerobic activity reduces feelings of anxiety. People who work out daily feel the biggest benefit, but just fifteen minutes of activity two or three times a week can lift spirits for two to four hours after exercise.

Even a single brisk walk around a park offers relief from temporary anxieties such as stage fright. Not long ago, researchers put young musicians from the Royal College of Music in London to the test. When they asked each student to perform for them, they found that pre-performance anxiety stepped up the students' heart rate by about 15 percent. Then the team requested a second performance, but instructed half of the students to walk for twenty-five minutes before performing again; the other half watched a video. The walkers had significantly lower heart rates and reported feeling more relaxed and better able to concentrate on their playing than their sedentary counterparts.

The temporary feel-good effect of vigorous exercise was once attributed solely to endorphins. It's true that prolonged cardiovascular exercise—running, rowing, cycling—increases endorphin levels by as much as two- to fivefold. It's also true that a rise in endorphins is often associated with improved mood. But it remains unclear whether the two phenomena are linked: According to some neuroscientists, endorphins circulating in the blood don't easily cross the semipermeable blood-brain barrier to reach the brain. The uplifting effect may be due to a boost in levels of other chemicals, such as noradrenaline, serotonin, and dopamine—that chemical active in stimulating the brain's reward center. Most likely the mood lift comes from the interaction of all these chemicals and others, according to John Ratey, a professor of psychiatry at Harvard University. A bout of brisk exercise, says Ratey, is not unlike taking a bit of the attention-enhancing Ritalin and a bit of the antidepressant Prozac and putting them right where they need to go.

In fact, when it comes to relieving the symptoms of depression over the long term, regular moderate exercise may work as well as drug therapy. In a study called
SMILE
(Standard Medical Intervention and Long-term Exercise), James Blumenthal and a team of researchers at Duke University discovered that vigorous walking, jogging, or biking for thirty to forty-five minutes, three times a week, is at least as effective as powerful antidepressant drugs at lifting major depression and keeping symptoms at bay.

The team studied adults over the age of fifty who suffered from major depression. The subjects were divided into three groups: the first received medication; the second, a combination of medication and an exercise program; and the third, an exercise program only. After four months, subjects in all three groups reported fewer symptoms of depression. In follow-up studies over the next several months, the exercise group had lower relapse rates than the medication group.

Physical activity also offers relief for those with only mild to moderate depression. One study found that patients who worked out for a half hour three to five times a week said they had half as many depressive symptoms as they had before they began their exercise program.

It's hardly surprising, then, to find a flip side to this phenomenon. A longitudinal survey of more than 6,800 men and women showed that physical
inactivity
is associated with more depressive symptoms and lower feelings of emotional well-being.

How might exercise work its deeper mood magic? Some scientists speculate that improved aerobic fitness does the trick, or possibly a reduction in the amount of
REM
sleep one gets at night (which may be the way that some antidepressant drugs work, too). Blumenthal suspects that people who exercise may also feel more of a sense of mastery and self-confidence, the perception of being in control—doing something positive and health-promoting, he says—which translates into improved mood.

Even if you're not stressed out or depressed, there's another good reason to duck out of the office and head straight for the gym: Late afternoon and early evening are considered the optimal hours for many kinds of athletic activities. Your body is generally at its physical best late in the day. Your perception of exertion is low. Your muscles are most powerful and your joints most flexible. Your hands and your back are about 6 percent stronger than they are early in the day.

A late workout also better benefits muscle-building. Exercise in the evening, and you may gain as much as
20
percent more muscle strength than you would if you trained in the morning. At the end of the day you also literally breathe easier: Airways are most open late in the afternoon. Moreover, the heart works more efficiently, and reaction time is at its peak. This has to do in part with core body temperature, which typically rises across the day to peak in the late afternoon or early evening. For every i° C rise in body temperature, heart rate increases by about
10
beats per minute, and the speed of nerve conduction quickens by
2.4
meters per second.

For all of these reasons, most sports records are set between 3
P.M.
and 8
P.M
. Swimmers swim faster then; runners run faster. For elite athletes, training and performing at these optimal times may bring some advantage. For the rest of us, exercise often just feels easier later in the day.

Still, if you're wedded to an early workout, don't despair. Studies suggest that morning trainers can reach higher work rates. Early in the day, when body temperature is relatively low, you may start at a lower work-rate level than afternoon trainers, but it will build gradually until your body temperature reaches its optimal level. By the end of the training session, you'll be working harder than late-day trainers.

Also, back pain is often less severe early in the day. Our erect posture subjects the disks of our backbone to pressure equal to several tons per square inch. This pressure can squeeze nerves leading from the spinal cord, causing back pain that tends to worsen late in the day, as gravity during our upright hours effectively compresses the space between the disks. By contrast, the spinal column lengthens at night, when we "unload" it by getting horizontal during sleep. As a result of this unloading and lengthening, body height peaks in the morning (by a fraction of an inch), and back pain eases.