Why do we feel pain and how physical activity can help

Why does pain show up the way it does? Why does it linger for some people and disappear quickly for others? Can movement, even gentle movement, help?

In this episode of Let’s Talk Health, Tim Trevail, Pain Specialist, unpacks the science of pain, the role of the brain, and why physical activity is one of the most powerful tools we have for managing persistent pain.

Pain and the brain

One of the biggest misconceptions about pain is that it’s purely physical and that pain equals damage. But as Tim explains, pain is far more complex and far more human than that.

Pain is universal, but it’s also deeply individual. Two people can have the same injury but experience completely different levels of pain. That’s because pain isn’t just about what’s happening in the body, it’s also shaped by our emotions, environment, stress levels, and beliefs.

“Pain is an unpleasant sensory and emotional experience associated with actual or perceived tissue damage.” - Tim Trevail

That emotional component is key. We now know that pain cannot occur without passing through the emotional centres of the brain. This is why two people with the same injury can have very different experiences, and why your own pain can feel worse on some days and better on others.

Can the brain feel pain?

Interestingly, the brain itself has no pain receptors. So why do we get headaches? Because the brain interprets signals from surrounding tissues, including blood vessels, nerves, membranes and creates the experience of pain. Pain is the brain’s protective alarm system, not a direct measurement of damage.

Can you train your brain to not feel pain?

You can’t “switch off” pain entirely, but you can retrain your brain to interpret signals differently. This is the foundation of modern pain science:

• Movement
• Stress reduction
• Education
• Building confidence in your body

These all help the brain dial down the “volume” of pain over time.

Stress and anxiety worsen pain

If pain is the body’s alarm system, stress is like someone turning the volume knob all the way up. Tim explains that the brain constantly modulates pain - turning it down when we feel safe, and turning it up when we’re stressed, anxious or overwhelmed.

When stress is high, the brain becomes laser‑focused on survival. It’s less able to filter out pain signals, which means even small sensations can feel amplified.

This is why chronic stress, anxiety and depression often go hand‑in‑hand with chronic pain.

“So if it's like a radio, you've got a volume knob on that radio, you can either dial those things down by suppressing some of those signals coming up, or it can dial them up and amplify those signals.

"When you've got stress and anxiety, the brain is focused on simple must-do tasks right now, and it's not as good at dialling down some of those pains, those feedback signals that are coming up to the brain. Managing stress and managing that anxiety is an important part of pain management,” Tim says.

It also explains why people sometimes become fearful of movement. They worry that bending, lifting or twisting will cause more damage, even when the tissue has healed. This fear can lead to stiffness, guarding, and reduced mobility, which ironically makes pain worse.

Movement should be free and thoughtless. When we tense up, brace, or overprotect an area, we increase pressure on pain‑sensitive nerves. For many people, learning to move more freely and less rigidly is the key to reducing pain.

How a sedentary lifestyle can contribute to pain

Modern life has changed the way we move. Many of us spend long hours sitting at desks, working from home, or glued to screens. And while posture itself isn’t “good” or “bad,” staying in one position for too long can irritate muscles, joints and nerves.

“We used to have a concept that pain is really about biology and it's about how things might hurt as a direct result of an injury. But now we understand that it is deeply emotional. We can't have pain without it going through the emotional centers of the brain. And it's also very much driven by context and environment around us.” says Tim.

“Motion is lotion, rest is rust”

Across Western countries, around 20% of people experience persistent pain and much of it musculoskeletal. Sedentary lifestyles are a major contributor.

Think about a typical workday:

• Hours sitting at a desk
• Minimal incidental movement
• Long periods without stretching or walking

During COVID, many people noticed their pain increase simply because they were moving less. Without the natural movement that comes from commuting, walking between meetings or getting up from your desk, the body becomes deconditioned and pain becomes more likely.

Why are pain and pleasure so close?

Pain and pleasure share overlapping pathways in the brain. Both involve the limbic system (the emotional centre), which is why strong emotions can intensify pain or when you are happy and relaxed, pain may seem less.

This overlap also explains why activities like exercise, laughter, social connection and even music can reduce pain. They activate the brain’s reward pathways, releasing endorphins and calming the nervous system.

How physical activity and exercise can relieve pain

If you live with persistent pain, the idea of exercising might feel intimidating. But movement is one of the most effective tools we have - not because it “fixes” tissue, but because it retrains the brain.

Tim explains that any movement counts. There is no single “best” exercise for pain. What matters is consistency and enjoyment.

Examples of pain‑friendly movement

• A 30‑minute walk
• A 15‑minute brisk walk or jog
• Yoga or Pilates
• Dancing
• Swimming
• Martial arts
• Gardening
• Cycling

If it gets your heart rate up and feels manageable, it’s helpful.

Strength training matters too

From around age 30, we naturally lose muscle mass. Strength training twice a week helps maintain muscle, protect joints, and reduce the risk of falls and fractures - especially for women.

How much movement is enough?

Tim’s research shows that people with persistent pain benefit from:

• 6,000 to 7,000 steps per day
• Regular strength training
• Movement that feels safe and enjoyable

More steps can help, but the biggest improvements happen between the 6,000 and 7,000 step range.

Why movement reduces pain

Movement can interrupt the downward spiral from inactivity to stiffness to more pain. It can help with:

• Improving blood flow
• Reducing inflammation
• Releasing endorphins
• Building confidence
• Reducing fear
• Helping the brain reinterpret pain signals

Is pain all in your head?

Pain is always real. But it is also processed in the brain, which means it is influenced by:

• Emotions
• Stress
• Sleep
• Beliefs
• Past experiences
• Environment

Understanding this doesn’t make pain “imaginary.” It makes it treatable.

Pain doesn’t always mean damage

This is the myth Tim wants to bust most of all:

“If we believe pain equals damage, we become fearful, avoid movement, and lose confidence in our bodies. But for many people, especially those with persistent pain, the tissues have healed, it’s the nervous system that needs support. ”

Movement, education, and reassurance can help turn the volume down.

Listen to the full episode Let’s Talk Health with Tim Trevail to dive deeper into the science of pain and practical strategies to manage it.