Understanding Pain – What is pain and why does it persist?
Written by: Alister
Published on: October 7, 2020

What is pain?

Pain acts as our body’s “alarm system”. The innate design of pain is to create action and to ideally protect ourselves from danger. For example, with many acute injuries such as a broken leg, experiencing pain is very useful as it stops us from walking on an injured body part and avoiding further damage.

However, our pain alarm can keep going off long after it has served its useful purpose of protection. This long term pain alarm can become a separate issue from the initial injury or problem. Our pain alarm can sometimes act in the same way as a smoke alarm.

Smoke alarms are designed to alert us to the danger of fire, but it can not distinguish between burning your toast (low threat) or a house fire (high threat). Even after the fire has been put out (danger has gone), smoke alarms can keep on ringing.

They aren’t exactly a good indicator of how much danger we are in, just like our pain alarm is not an accurate measure of damage occurring in the body.

Acute versus persistent pain

Whilst ‘acute pain’ and ‘persistent pain’ may feel the same, they are very different. Acute pain is short term that can last up to 3 months and is associated with damage or possible damage to our body. For example, if you sprained your ankle this would often cause pain and result in bruising and swelling.

As your body begins to heal this acute pain will usually subside as the body doesn’t need protecting anymore. Depending on the severity, most injuries will take less than 3 months to heal but some may take longer. However this does not mean you have to be in pain for this long! 

‘Chronic pain’ is a term that you may have heard which is often used to describe pain that lasts longer than the usual 3 month time frame for our body to heal. Many people think that this means that their pain is severe and will be something they will experience for the rest of their life.

This is not the case! A more appropriate term used to describe this is ‘persistent pain’ as it is pain that has persisted longer than what we expect it to. Persistent pain is complex. It can occur as a result of trauma, surgery or alongside conditions such as back pain, arthritis, osteoporosis, cancer and fibromyalgia. 

In Australia 3.37 million people live with persistent pain (1 in 5 over the age of 45) which has a significant impact on their quality of life, physical function, community and social engagement, work and education (1). Traditionally, the recommended treatment for persistent pain included rest and inactivity to reduce symptoms.

However exercise is now promoted in both the prevention and treatment of persistent pain as it may provide benefits for a range of associated health conditions (2). Exercise can reduce pain severity and sensitivity as well as provide general health benefits to improve physical and mental health, physical function and quality of life.

Why does pain persist?

A common misconception is that persistent pain is caused because an injury hasn’t fully healed yet or there is damage still occurring in the body. However, for most people it is now known that this is unlikely (3). So if persistent pain isn’t caused by injury or damage to the body then why does it feel like it? Well, persistent pain involves changes to the body’s central nervous system (the nerves, spinal cord and brain) that occurs over time and this increases the sensitivity to pain.

The nervous system becomes hypersensitive to pain and it is common to experience pain with usual everyday activities or tasks that may not have caused pain in the past. Think of it like your pain ‘alarm system’ being overprotective and going off when it doesn’t need to. This is not to say that persistent pain isn’t a physical experience, it very much is, but it’s important to address other factors that may be increasing your sensitivity to pain. 

It’s important to understand that you can drive down pain sensitivity and overprotection and get back to doing the things that you enjoy. But it will take time, effort and patience. Your general practitioner and the exercise physiology team at Revitalize can help to guide you in this process. If you would like to learn more, please go to the helpful resources links below. 

Helpful resources:



Written by Accredited Exercise Physiologist Alister MacInnes. 


  1. Painaustralia.org.au. 2020. Painful Facts. [online] Available at: <https://www.painaustralia.org.au/about-pain/painful-facts> 
  2. Geneen LJ, Moore RA, Clarke C, Martin D, Colvin LA, Smith BH. Physical activity and exercise for chronic pain in adults: an overview of Cochrane Reviews. Cochrane Database of Systematic Reviews. 2017(4).
  3. Fornasari D. Pain mechanisms in patients with chronic pain. Clinical drug investigation. 2012;32(1):45-52


Submit a Comment

Your email address will not be published. Required fields are marked *