Understanding how stress manifests in your mind and body is a great first step to better managing your stress levels.
A major part of our stress response is the hypothalamic-pituitary-adrenal (HPA) axis. When we encounter a stressor, be it physical danger or a looming deadline, the amygdala - the part of the brain that determines if there is danger - tells the hypothalamus to release corticotropin-releasing hormone (CRH). This signals to the pituitary gland to secrete adrenocorticotropic hormone (ACTH), which in turn prompts the adrenal glands to produce cortisol, a key stress hormone.
Cortisol plays a crucial role in preparing our body to face a challenge. It increases glucose in the bloodstream, enhances the brain’s use of resources, and slows down functions that are nonessential in a dangerous situation. This response, while life-saving in short bursts, can be damaging if activated for too long. Our body will attempt to prevent chronic activation through a negative feedback loop where increased cortisol levels also signal the hypothalamus to stop releasing CRH.
Another vital player in the stress response is the autonomic nervous system, specifically its sympathetic branch. The amygdala also activates the sympathetic nervous system (SNS) in response to danger, initiating fight-flight-freeze-or-fawn (“fight-or-flight” for short). The SNS signals the adrenal glands to release adrenaline (epinephrine) and noradrenaline (norepinephrine), thus increasing heart rate, blood pressure, and energy supplies. Like cortisol, these changes are all helpful for the physical responses that might be needed in a fight-or-flight response but can be harmful when chronically activated.
Fortunately, our body also has a built-in stress recovery system: the parasympathetic nervous system. Often referred to as the “rest and digest” system, it conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes muscles in the gastrointestinal tract. We can take command back over our thoughts and behaviors with techniques such as deep breathing, meditation, and moderate exercise. These support a healthy balance between the sympathetic and parasympathetic nervous system, helping to mitigate the effects of excessive stress. A balanced diet, adequate hydration and sleep, social support, and other self-care routines also bolster our resilience against the harmful effects of chronic stress.
In summary, the biology of stress reveals a finely tuned system designed to protect us. However, in our modern world, where stressors can be relentless and varied, it’s crucial to take proactive steps to manage our stress. Experiment with the ways that work best for you and adapt these methods if you find yourself feeling overwhelmed. By doing so, we harness the power of our biology to thrive in the face of challenges.
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