How does my body respond to stress?

The stress you know may look like this.

But did you know it can also look like this?

Recognizing the signs of stress response in the body can help you manage how you deal with stress.

According to the definition of stress in both psychology and biology, stress is a pattern of physiological responses to a threat or stressor.

The stress response is our body’s attempt to survive and cope with such threats.

The nervous system is the structure in our body that allows us to feel and deal with threats.

The nervous system is the body’s command and communication system.

It consists of the brain, spinal cord, and a network of nerves.

During stress response, these two nervous system's structures play a significant role:

Sympathetic Nervous System (SNS)

• controls the “fight or flight” response

• stimulates the body when facing a stressful situation

Parasympathetic Nervous System (PNS)

• controls the “rest and digest” function 

• relaxes your body after the stress has passed

The changes our body goes through when stressed can be explained using the 3 stages of the General Adaptation Syndrome (GAS).

When you encounter a threat, your senses send information to your brain, which triggers a stress response.

The SNS releases the hormone adrenaline into the bloodstream. It prepares the body to either fight or flee from the threat.

This can cause:

• Increased heart rate to push blood to vital organs

• Increased oxygen for the brain (alertness) and muscles (strength)

• Dilated pupils for better vision and awareness

• Sweat production to regulate body temperature

After the initial shock of stress, the PNS takes over and the body begins to “rest and digest.”

The body begins to slowly repair itself by normalizing biological responses. It may take a while for it to fully replenish the resources lost and return back to its pre-stress condition:

• Energy conservation

• Lowered heart rate

• Improved digestion

• Elimination of waste

However, if the stress persists for longer, the body will continue to stay on alert and move on to the next stage.

Prolonged or chronic stress causes the body to use up all its resources. At this point, it may no longer be able to deal with the threat.

This can look like extreme fatigue, burnout, and decreased stress tolerance.

Under chronic stress, cortisol (aka the “stress hormone”) levels remain high, which can cause:

• Headaches

• Increase or decrease in appetite

• Increased risk of health conditions

• Muscle pain

• Digestive problems

• Trouble sleeping

Jeremy just finished an important presentation at work.

Jeremy spent months working on and stressing over this presentation, so he's glad that he was finally able to finish it.

He has a bit of trouble shifting his focus to other tasks right away, but his pre-presentation jitters have stopped and his palms are no longer sweaty.

Understand the biology behind stress to better manage it!