What are the causes of pain?

For athletes and fitness enthusiasts or those hitting the gym for the first time, pain is no stranger. No pain, no gain, right? But what causes us to feel pain, are there different types of pain, and how can you describe your pain so your doctor can give you the best possible advice?

The point of pain

According to Dr Adriaan Liebenberg from The Pain Collective, we experience pain when specific nerves or pain receptors detect tissue damage and send a message along the spinal cord to the brain. It is our body’s way of warning us that something is wrong.

“Suppose you accidentally touch a hot stovetop. A message is immediately sent through a reflex arc in the spinal cord, which results in muscle contraction. This contraction will quickly and automatically pull your hand away from the hot surface to prevent severe burns.

“This reflex takes place even before the message reaches the brain. When the message reaches the brain, you experience an unpleasant sensation called pain. The brain’s interpretation of these messages and the speed at which the messages travel affect how a person experiences pain. The brain can also release feel-good chemicals such as dopamine to ease the experience of pain.”

Pain can occur in the short or long term, be limited to one place, or spread throughout the body, explains Dr Liebenberg. The experience of pain also varies from individual to individual. How someone experiences pain is influenced by the interaction of biological, psychological, and social factors (also called the biopsychosocial pain model) unique to each person.

Types of pain

He distinguishes between two main types of pain, namely acute and chronic pain.

Acute pain

This type of pain, which is generally intense and short-lived, is the body’s way of making you aware of an injury or tissue damage. Although acute pain triggers the body’s fight-or-flight response (which can lead to a faster heart rate and breathing rate), it is usually quickly resolved with self‑treatment or medicine. Acute pain is a useful physiological response and can be divided into:

• Somatic pain

  This is superficial pain on the skin or the soft tissue just below the skin.

• Visceral pain

  This pain originates in the internal organs and the lining of cavities in the body.

• Referred pain
  A person experiences pain in a different place than the source of the tissue damage. For example, people often experience shoulder pain before or during a heart attack. A special type of referred pain is experienced when a nerve is pinched. The most common type of pinched nerve pain is called sciatica.

Chronic pain

Chronic pain can be moderate or severe and is pain that is present for more than three months, says Dr Liebenberg. “There is usually no cure for this, as the pain represents the symptom of an underlying issue. It can be continuous, as with arthritis, or intermittent, as with migraines. Over time, the electrical signals can build up in the central nervous system, overstimulating the nerve fibres.

“This is known as the wind-up effect. Think of a wind-up toy. The more the toy is wound up, for example, the longer it will spin around or the further the toy car will travel. Chronic pain works in the same way. This is why a person can still experience pain long after the event that initially caused the pain. Chronic pain is an abnormal, non-useful physiological response.”

Other specific types of pain

Always tell your doctor or therapist everything you feel, so that they can make the best possible diagnosis, says Dr Liebenberg. Other specific types of pain include:

• Neuropathic pain
  This occurs after an injury to the nerves that connect the brain and spinal cord to the rest of the body. It can feel like electric shocks or cause tenderness, numbness, tingling, or discomfort.

• Phantom pain
  Phantom pain often occurs after the amputation of a limb. It refers to a painful sensation that feels as if it comes from the amputated limb.

• Central pain
  This occurs as a result of infarction (obstruction of blood flow to organs or tissue), abscesses, tumours, degeneration (deterioration or aging), or bleeding in the brain and spinal cord. People with central pain usually experience a burning, aching, or pressing sensation.

Good pain

Believe it or not, there is such a thing as good pain! Dr Liebenberg explains, “The best example is the burning muscle pain you experience when you do weight training in the gym, jog, or cycle. This burning sensation usually disappears when you put the weights down, hit the brakes, or catch your breath. This is caused by the build-up of lactic acid, a natural by-product when carbohydrates are converted into energy.”

Ever get a pain in your side when you jog? This pain, which we colloquially call stitch, is a condition called exercise-related transient abdominal pain (ETAP). It feels like a sharp stabbing pain, but can also be experienced as a dull pain, cramps, or a pulling sensation. Although it might feel like you’re dying, it isn’t a cause for concern. It usually blows over after you take a break.

The delayed onset of muscle soreness (DOMS) is another example of good pain. It’s actually just sore muscles and commonly occurs a few hours to a day after exercise. DOMS is often experienced when you start a new exercise that your body is not used to or when you increase the intensity of your workouts.

On a microscopic level, DOMS is an injury to the muscle fibres and connective tissue. The pain usually disappears quickly and will not interfere with your daily activities or impede your mobility.

When pain isn’t physical

Psychosomatic pain is a pain disorder caused by excessive stress or a mental condition. “It is characterised by headaches, stomach aches, muscle pain, and back aches. The pain originates from an issue in the psyche – such as depression, anxiety, or stress – and then spreads to the musculoskeletal system of the body. Psychosomatic pain is difficult to diagnose because all possible physical causes must first be eliminated. Treatment includes antidepressants, psychotherapy, pain medication, or relaxation techniques. The best treatment usually involves a combination of medical and mental health care,” he concludes.