Research explores how exercise can protect against the harmful effects of chronic stress.
Think of a recent time you felt stressed. Maybe it was during an argument with your spouse, or a meltdown with your kids. Maybe you were stuck in traffic and late for an important meeting. Or maybe you were lying in bed, worrying about work. Whatever the cause of your stress, your body and brain were almost certainly experiencing the same thing: boiling blood pressure, a churning stomach, tight muscles and a racing mind.
We all recognize this feeling of stress. It’s more than a mental state; it’s a full-blown mind-body response. When stress takes hold, the brain is bathed in chemicals that heighten our senses and focus our attention, making it impossible for us to think about anything else. The sympathetic nervous system gets a jump-start, and stress hormones like adrenaline and cortisol make us feel even more wired. Glucose and fats flood the bloodstream, and our cardiovascular and respiratory systems rev up, all to give us the energy we need to deal with the stress.
These changes would make sense if we were running for our lives or rescuing our child from a fire. But when everything from taxes to television news triggers a reactive response, stress becomes toxic. Chronic stress increases the risk for a wide range of health problems, in large part because the body’s response to stress adds up over time (McEwen 2006). Chronic inflammation and sympathetic activation contribute to autoimmune disorders, chronic pain and cardiovascular disease. Elevated blood glucose and fat levels raise the risk of insulin resistance and diabetes. Chronic exposure to stress hormones suppresses the immune system, kills off brain cells and promotes obesity. When any unwanted physical or psychological condition is present, chances are that stress plays a role.
And yet, not everyone is equally susceptible. Some people seem to be protected from the worst effects of stress. These resilient folks handle stress better and recover from stress more quickly. Science is beginning to reveal the secrets of stress resilience and to learn what it looks like in the brain and body. It turns out we can measure stress resilience in the heart, the nervous system (which includes the brain) and even our DNA. We can also train resilience—even in the face of chronic stress.
This article explores the new biology of stress resilience, how it protects against stress-related diseases, and why exercise may be the best way to train it.