Workout Stress Test

While everyone who lifts weights wants to look better, health benefits are a major accessory to an improvement in body composition. Initially, research showed that doing aerobic exercise had potent preventive effects against cardiovascular disease. More recent studies have proven that lifting weights replicates many of the cardiovascular protections you get from aerobic training. An often overlooked effect of exercise is its role in stress reduction.

Whether stress is good or bad news for your health depends on how you perceive stress. What’s stressful to some may be invigorating to others. Still, in today’s fast-paced society, it’s nearly impossible to avoid negative stressors that take a toll on health. Merely listing stress-related diseases would fill a magazine article. Suffice it to say that unchecked stress plays a major role in disease—even longevity.

When scientists look at factors associated with longer life span, stress is always one of them. In the brain, lifetime release of the stress hormone cortisol selectively destroys cells in the areas associated with learning and memory. The memory lapses that gradually increase with age—so-called senior moments—are often linked to recent stressful events. Older people who remain healthy, with full cognition, usually are those who are not overwhelmed by stress, instead taking things as they come. They don’t succumb to stress-related maladies, including cardiovascular disease.

Exercise helps because it provides an avenue for stress release. To be sure, exercise itself is a form of stress, but it’s categorized as a “eustress,” or stress that is beneficial, as opposed to negative stress. On the other hand, exercise can easily turn negative if you overtrain, which releases an excess of stress hormones, such as cortisol. Among the functions of cortisol are its ability to break down muscle protein, leading to muscle loss. A less severe symptom is a lack of regular gains in muscle size and strength.

Since training itself is a form of stress, many scientists suggest that it conditions the mind and body to deal with other forms of stress in life, particularly mental stress.Whether training does help in that regard was the question posed by a recent study. Twenty-two trained elite athletes were compared with 22 untrained men after both groups were exposed to psychological tests used to measure mental stress response. The subjects were tested for salivary cortisol levels, heart rate and various psychological responses, such as mood, calmness and anxiety, before and after stress exposure.

The trained men showed less cortisol and lower heart rates than the untrained men when both groups were exposed to stress. Under high-stress conditions the trained men were calmer and had significantly less anxiety than the untrained men. The authors suggest that trained men view stress as less threatening and more controllable than untrained men do. Animal-basedstudies show that whether stress induces illness depends on how it’s perceived—the keynote being the belief that stress is controllable. If you think that imposed stress can’t be dealt with, it turns deadly.

Scientists who study the effects of stress say that regular exercise produces a sense of mastery that becomes dominant in all aspects of life. Indeed, Arnold Schwarzenegger frequently attributes much of his success to the self-confidence and discipline that he developed from his years of competitive bodybuilding. Arnold is widely reported to be particularly adept at handling stress in his life.

Exercise produces many of the hormone and biochemical changes that occur with other forms of stress, and its effect is that when you train, you’re conditioning both your mind and your body against the onslaught of stress. So when negative stress does occur, you’re far more prepared to deal with it. You can ride the wave of stress reactions with little or no negative consequences. That, in turn, leads to more self-confidence under high-stress conditions, which leads to less stress, and so on.

Regular training also leads to less cortisol release during workouts. It’s a case of conditioning, in which the body adapts to the imposed stress of exercise. It also explains why beginners have far more cortisol than more-advanced trainees—and why certain food supplements, such as HMB, a branched-chain amino acid derivative, work for beginners but not for those who are more advanced. Ditto for protein supplements: They, too, produce better results for beginners precisely because novice trainees produce more cortisol after training, and protein negates the rise in cortisol.

Rimmele, U., et al. (2007). Trained men show lower cortisol, heart rate, and psychological responses to psychosocial stress compared with untrained men. Psychoneuroendocrinology. 32:627-35. IM