What No One Tells You About Lower Back Pain

21 June 2021

Lower back pain often associated with weak lower back muscles. Contrary to that belief, low back pain caused by excessively tense muscles, as a result of fear of pain and avoidance behaviour.

Erector Spinae Muscles

A common feature when it comes to the discussion of lower back pain is the Erector Spinae muscle. (Refer to fact box). When this group of muscle tenses constantly, it becomes tight and is unable to relax. This leads to the arched back posture that people suffering from low back pain can have. This tensed muscle will limit a person’s movement into flexion or otherwise in layman’s term- bending forward, due to fear or pain.

How does the physiotherapist find out your muscles restricted because of fear or pain?

In order to assess this, a physiotherapist will carry out what known as Flexion Relaxation Response (FRR). FRR involves the eccentric contraction of the erector spinae which helps the patient to achieve their full range.

This occurs until the end of the range where muscle activity decreases significantly. The spinal extensors then relax completely, leaving the flexion torque supported by the spinal ligaments.

Erector Spinae Muscle

  • A set of three overlapping groups of deep muscles highlighted in illustration (Iliocostalis, Longissimus, and Spinalis)
  • Situated along the spine
  • Forms the largest area of muscle on the posterior (back) of the human torso
  • These muscles vary in size and structure at different parts of the vertebral column
  • Erector Spinae muscles function to straighten the back and provide for side-to-side rotation

What causes this movement impairment?

As soon as it established that FRR impaired, we need to examine the factors that limit the muscles from relaxing. Musculoskeletal conditions are often complex in nature and limiting factors can occur concurrently. It is primarily due to fear avoidance behaviour- that is limiting one’s flexion deliberately for fear of pain. This results in stiff joints in the lower back and hips as well as tight and tense muscles in these two areas.

The tightness can be a sign of guarding, which a maladaptive movement orchestrated by the brain. Guarding occurs out of fear which stems from a faulty belief system. An example of a faulty belief is that a disc can “pop” out if I bend forward, and it can “pop” back in if I arch my back.

Prior to engaging the lower back, the brain increases muscle activity to protect the body region. This is your body’s automatic mechanism to counter the ongoing pain that you are experiencing.

A specific example where guarding takes place on the lower back when the erector spinae remains active and engaged even as the spine is flexed forward.

The muscles should switch off. The fact that it still actively engaged is an indication of an abnormal movement and there needs proper intervention to address it.

What can I do to relax the tense low back muscles (pain)?

It is important to find the root cause of why your muscles are tense and working too hard. How then do we treat such a condition? It has to be understood that treatment is never a ‘one size fits all approach. Adequate and accurate assessments coupled with clinical reasoning needs to be applied in order to choose the appropriate treatments for you.

A physiotherapist has to understand your conditions first before providing solutions. Also, it is not just the physical aspect that matters. There needs to be adequate support for mental wellbeing which promotes optimal recovery.

A combination of cognitive-behavioural interventions with pain reduction strategies is part of a holistic approach to managing persistent pain.

So the next time you are experiencing lower back pain, it could possibly stem from your body’s behaviour and movements.

Watch this video to find out more about the different types of back pain. It should always be kept in mind that back pain is a personal and complicated experience for each individual. Seeking medical advice and opting for treatment from a professional may be the solution to manage your back pain woes.

Experiencing back pain? Find out more how Core Concepts Physiotherapy Singapore can help resolve your pain.

Spine-heath: Different Types of Back Pain Explained


  1. Muscle Used (2013). Erector Spinae
  2. O’Sullivan, P. (2005) Diagnosis and classification of chronic low back pain disorders: Maladaptive movement and motor control impairments as underlying mechanism. Manual Therapy, Volume 10, Issue 4, 242 – 255
  3. Smale, S. (2016). Flexion Relaxation Response & Low Back Pain. Rayner and Smale
  4. Back Pain Image Courtesy of stockimages at FreeDigitalPhotos.net
  5. Erector Spinae Image By Henry Vandyke Carter – Henry Gray (1918) Anatomy of the Human Body