What is the stress response? 

• The stress response is your body’s automatic reaction to a perceived threat, challenge, or demand, helping prepare you to respond to what’s happening.
• Stress can be triggered by physical threats as well as everyday pressures, with your body responding through changes such as increased alertness, heart rate, and breathing.
• The stress response moves through activation, peak, and recovery, with your body gradually settling once the stressor has passed.
• Regular movement, good-quality sleep, rest, and slow breathing can give your body opportunities to recover between everyday stressors.

Your heart starts beating faster before an important meeting. Or you feel your whole body tense when something catches you off guard. These reactions can happen quickly, sometimes before you’ve had much time to think about what’s going on.

They’re all part of your body’s response to stress. When your brain detects a potential threat, it sets off a series of changes that are designed to help you respond¹ ². Your nervous system becomes more alert, stress hormones are released, and things like your heart rate and breathing can shift.

While it may feel uncomfortable, the stress response is a normal part of how the body adapts to a challenge¹ ². Once the immediate stressor has passed, your body will gradually return to its usual resting state¹.

In this guide, we’ll take a closer look at how the stress response works, what can trigger it, the physical and mental signs you might notice, and some practical ways to support recovery.

What is the stress response?

The stress response is your body’s automatic reaction to a perceived threat, challenge or demand¹ ². It involves changes across your nervous system and hormones that prepare you to deal with the situation. 

Your stress response can kick in during a physical threat, but everyday situations can also set it off. A difficult conversation, a looming deadline, or an unexpected problem can all put your body on alert. When this happens over a short period, it’s known as the acute stress response¹.

Once the threat or stressful situation has passed, your body begins to settle again. The parasympathetic nervous system helps bring your body back to a calmer state¹. Remember that it's normal to feel stress, but it's just as important that your body can recover once the stress has passed. 

What happens in the body - the fight or flight response

Your body’s stress response can happen quickly. So, what’s actually going on behind the scenes? 

The fight-or-flight response begins when your brain detects a stressor, whether that's a physical threat or a psychological challenge¹ ³. 

From there, two systems get to work. The sympathetic-adreno-medullary (SAM) system helps drive the initial response, including the release of hormones such as adrenaline. Then the hypothalamic-pituitary-adrenal (HPA) axis follows with a slightly slower response that includes the release of cortisol¹ ³.

These two changes help prepare your body to deal with what’s happening. Your heart rate and breathing can increase; you may feel more alert, and more energy is available to help your brain and muscles respond³.

This is the acute stress response in action. It’s designed to be short-lived and useful in the moment, giving your body the resources it needs to deal with a threat³. 

What triggers the stress response?

The stress response can be triggered by anything your brain perceives as a threat, challenge, or demand¹. Sometimes the trigger is obvious, like being in physical danger. Other times, it can come from mental or emotional strain, whether at work or home.  

Your brain can react to psychological stressors in many of the same ways it reacts to physical challenges¹. It can set into motion a stress response, even when there’s no physical danger in front of you. 

Heavy workload, conflict with someone close to you, a physical threat can all be triggers. However, exact triggers can look different from person to person. A situation that feels stressful to you might feel manageable to someone else. 

Recognising stress response symptoms

Stress response symptoms can show up in your body, thoughts and emotions, and they can look a little different from person to person. 

Some common signs can include:

• Physical: a racing or pounding heart, tense muscles, chest tightness, nausea, dizziness or feeling light-headed⁴ ⁵
• Cognitive: racing thoughts or finding it harder to concentrate⁵
• Emotional: feeling irritable, on edge, or unusually alert⁵

These symptoms can overlap. Your heart rate may change, for example, while stress can also affect your digestive system and make it harder to concentrate⁴ ⁵. 

If the stress response stays activated for longer periods or is triggered repeatedly, it may be an overactive stress response. This generally describes a stress response that stays switched on for longer or is activated repeatedly, leaving your body in a more heightened state⁶.

It’s important to remember that these symptoms aren’t unique to stress. A racing heart, dizziness, nausea, or difficulty concentrating can have many possible causes⁴ ⁵. If your symptoms are new, severe, persistent or concerning, speak with a healthcare professional. 

Can the stress response cause chest tightness, nausea or dizziness?

Yes, chest tightness, nausea and dizziness can occur during a stress response⁴ ⁵. Stress can affect your breathing, heart rate, and digestive system, which may cause these physical sensations. 

However, these symptoms can also have causes unrelated to stress. If they happen frequently, feel severe, appear without a clear stress trigger, or are causing concern, it’s important to seek medical advice rather than putting them down to stress alone.

The stress response cycle 

The stress response cycle can be thought of in three states: activation, a peak in response, and then recovery⁷ ⁸.

• Activation is when something triggers your stress response. Your body becomes more alert and starts preparing to deal with whatever is happening.
• Peak is when the response is at its strongest. You might notice physical symptoms as your body responds to stress⁷.
• Recovery begins once the stressor has passed. Your body starts to settle, gradually moving from that heightened state back towards baseline.

Of course, everyday stress doesn’t always happen one thing at a time. Traffic on the way to work might be followed by a busy inbox, back-to-back meetings, and another problem before you’ve had much chance to reset. When stressors keep coming, your body may have less opportunity to fully recover between them⁸ ⁹. 

Over time, repeated or prolonged stress can make recovery more difficult and contribute to the effects associated with chronic stress⁷ ¹⁰. Making time to unwind can give your body a break between stressful periods. 

How to support your body's stress response naturally 

You can’t always control what causes stress, but you can build habits that give your body the chance to recover afterwards. Some healthy ways to respond to stress include regular movement, slowing down your breathing, making time for rest, and getting enough sleep¹⁰ ¹¹ ¹².

A few simple places to start include:

• Get moving: Physical activity can help break up periods of stress and give you a change of pace. Research also suggests that combining movement with slow-paced breathing may help support your body¹¹ ¹².
• Slow your breathing: Taking a few minutes to breathe more slowly and steadily can help your body shift towards a calmer state¹¹ ¹².
• Make room for rest: You don’t need to clear your whole day to take a break. Even stepping away from ongoing demands for a short time can give you a chance to reset. 
• Protect your sleep: Sleep gives your body and brain an important opportunity to rest and recover. Making enough time for sleep and keeping a regular wind-down routine can help support you through busy or stressful periods¹⁰. 
• Build routines that work for you: Regular meals, movement, downtime, and sleep can bring some consistency to busy days and make recovery part of your everyday routine. 

There’s no single right way to manage stress. The goal is to find realistic habits that help you manage everyday periods of stress. 

The stress response and your everyday wellbeing 

Stress is part of life, and your body’s stress response has an important job to do. It helps you react to challenges as they happen, before your body begins to settle again¹ ⁷.

Understanding what’s happening in your body can make those reactions feel a little less mysterious. It can also help you recognise when stress is building and when you might need to make more time for rest and recovery.

Supporting your wellbeing isn’t about eliminating stress altogether. Understanding your own stress response and making time to reset can help you navigate the everyday ups and downs can all help you look after yourself through the everyday ups and downs.

For more practical ways to support your wellbeing, explore articles including what is stress and a guide to adrenal fatigue on the Swisse Wellness Hub.

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