Inactivity and Low Back Pain

Introduction[edit | edit source]

According to NICE Guideline,p ublished in30 November 2016 and updated in December 2020 , the lower back can be defined as the area between the 12th ribs and the buttock creases.[1] "Non-specific" low back pain is defined as low back pain not attributable to a recognisable, known specific pathology (e.g. infection, tumour, osteoporosis, fracture, structural deformity, inflammatory disorder, radicular syndrome, or cauda equina syndrome).[2]

The time frame of low back pain classification:[3]

  • Acute low back pain – symptoms less than 6 weeks
  • Sub-acute low back pain – symptoms last between 7-12 weeks
  • Chronic low back pain – symptoms last more than 12 weeks


You can find guidelines regarding low back pain here.

Physical Activity and Inactivity[edit | edit source]

Physical activity is defined as any bodily movement produced by skeletal muscles that results in energy expenditure.”[5] Physical activity includes activities of daily living, such as walking, housework, gardening, and work-related activities.[6] When an individual does not meet the recommended level of physical activity, he or she will be classified as physically inactive.

The main focus of our page is physical inactivity is the cause of low back pain

The 2013 NICE Guideline recommendations (UK Chief Medical Officers’ physical activity recommendations) for physical activity state the following:[6]

  • All adults aged 19 years and over should aim to be active daily
  • Over one week, daily activity should add up to at least 150 minutes (2.5 hours) of moderate intensity physical activity in bouts of 10 minutes or more
  • Alternatively, comparable benefits can be achieved through 75 minutes of vigorous intensity activity spread across the week or combinations of moderate and vigorous intensity activities
  • All adults should also undertake physical activity to improve muscle strength on at least 2 days per week
  • All adults should minimise the amount of time spent being sedentary (sitting) for extended periods
  • Older adults (65 years and over) who are at risk of falls should incorporate physical activity to improve balance and coordination at least 2 days per week
  • Individual physical and mental capabilities should be considered when interpreting the guidelines, but the key message is that some activity is better than no activity

The World Health Organisation (WHO) has classified physical inactivity into two levels.

  • Level 1 exposure (inactive): an individual does very little or no physical activity at home, work, for transport or in his/her private time
  • Level 2 exposure (insufficiently active): an individual does physical activity less than 150 minutes of moderate-intensity or 60 minutes of vigorous-intensity physical activity in all activities of daily living.[7]

The current levels of physical inactivity are partly due to insufficient participation in physical activity during leisure time and an increase in sedentary behaviour during occupational and domestic activities.[8]

Sedentary Behaviour[edit | edit source]

National guidelines classify people as sedentary when an individual does less than 30 minutes of moderate activity on all or most days of the week.[9] Sedentary behaviour describes activities that do not increase energy expenditure significantly above the resting level. It includes activities such as sleeping, lying, watching television ,and other types of screen-based entertainment. However, light physical activity is often mistaken as sedentary behaviour, such as slow walking, sitting, writing, and cooking, but these do require energy expenditure above the resting level.[10]

Low Back Pain- Statistics[edit | edit source]

  • One-third of the United Kingdom adult population is affected by low back pain each year
  • 20% (1 in 15 of the population) of people will consult a GP about their low back pain[1]
  • In Europe, the lifetime prevalence of low back pain can be as high as 84%
  • After the first experience of low back pain, 44-78% of people suffer for relapse of pain again
  • 26-37% of people will have relapses of work absence after an initial episode of low back pain
  • Evidence has shown that the prevalence of chronic non-specific low back pain is around 23%, and 11-12% of the population is disabled by this condition[11]
  • 85% of cases are classified as non-specific low back pain as a diagnosis cannot be made by radiological methods[12]

Regarding IASP (International Association for Study of Pain):

"Low back pain is a common global problem.  The point prevalence of LBP in 2017 was estimated to be about 7.5% of the global population, or around 577.0 million people [2].

LBP has been the leading cause of years lived with disability (YLDs) since 1990 [2] and remains a significant global public health concern.

85-95% of people presenting to primary care providers do not have a specific identifiable pathoanatomical origin for their pain [3].

The proportion of people presenting to primary care with a specific identifiable cause of LBP is estimated to be 0-7-4.5% with osteoporotic vertebral fractures, 5% with inflammatory spondyloarthropathies4, 0.0-0.7% with malignancy, and 0.01% with infections.

The global burden of disability associated with LBP has been increasing since 1990.

Disability associated with LBP increased in all age groups between 1990 and 2019 and was greatest in the 50-54 age group in 2019. Approximately 70% of years lost through disability were in working-aged people (20-65 years)

There have been increases in both the number of people living with LBP and the prevalence of LBP in all age groups from 1990 to 2017. Although the prevalence of LBP increases with increasing age until 80-89 years, the greatest number of people with LBP globally are currently in the 50-54 year age group.

The overall increase in the burden of LBP is likely to be driven by ageing and an increasing population, however, there may be other contributing factors ."

Physical Inactivity[edit | edit source]

  • Around the world, one in five adults is considered physically inactive
  • In developed countries, physical inactivity was found to be more prevalent in women and the elderly
  • Female physical inactivity was higher (21.4%) than male (18.9%)[13]
  • Approximately 60% of male adults, 72% of female adults, 68% of boys, and 76% of girls aged 2-15 do not meet the UK Chief Medical Officers’ physical activity recommendations[14]
  • Physical inactivity has been reported as the fourth leading risk factor for global mortality (6% of deaths worldwide)[15]
  • Around 3.2 million deaths each year are related to insufficient physical activity[16]

Health Complications[edit | edit source]

Physical inactivity and sedentary behaviour can contribute to the following:[16]

Physical Activity- outcome measures[edit | edit source]

The outcome indicator should be chosen according to how well it measures the objectives of the study. Other important factors in choosing an outcome measure are the level of data required, the characteristics of the individual, group or population, time frame of interest, and the available time and resources.[17]

Physical activity can be classified as a combination of frequency, intensity, and duration. Any type of activity can be different in terms of the three different aforementioned elements. A better understanding of what element or activity that a study is focused on, the easier it is to determine what outcome measure is most appropriate.[18]

Measurement of physical activity can be challenging. The outcome measures for physical activity are generally of two types:

  • objective measures (e.g. accelerometers, pedometers, heart-rate monitors, armbands )
  • subjective measures (e.gself-report questionnaires, self- report Activity Diaries/Logs, Direct Observation).

Each has a different degree of validity (i.e. the extent to which an instrument genuinely records what it is intended to measure),[19] reliability (i.e. how consistently an instrument or tool will measure something on two or more separate occasions),[20] feasibility and practicality. However, there is no ‘gold standard’ for assessing physical activity in public health settings.[21][22][23]

Below are the options for measuring physical activity suggested in the Standard Evaluation Framework for physical activity interventions, published by the National Obesity Observatory.

  • The measure of a specific type of physical activity
  • Measure of the total physical activity
  • Proportion achieving recommended physical activity levels
Outcome measure.jpg

Public Health England published Standard Evaluation Framework for Weight Management Interventions in February 2018.

Self-report approaches are the most frequently used method for measuring physical activity in a public setting due to its cost effectiveness compared to other outcome measures. However, their reliance on recalling activity can be problematic, especially for children and young peopSelf-reportport of physical activity is subject to a number of types of bias, such as recall bias, lack of compliancedesirability desirability’ bias.[24]

Below is a short list of selected questionnaires for physical activity and diet:[25][26]

Children and Young People


  1. The Physical Activity Questionnaire for Older Children/Adolescents (PAQC/PAQ-A)
  2. Youth Risk Behaviour Surveillance Survey (YRBSS)
  3. The Teen Health Survey

  1. Stanford 7-day recall (7-DR)
  2. International Physical Activity Questionnaire Long version (IPAQ-Long)
  3. New Zealand Physical Activity Questionnaire (Short Form) (NZPAQ-Short)
  4. 7-day Physical Activity Diary

A systematic review by Falck et al. 2015 evaluated the measurement tools used in interventions to increase physical activity among older adults, including both objective and subjective measures. 44 studies were included, with 32 of them using self-report measures, 9 using objective measures, and 3 using both. Among all the measures, only 57% of them had population-specific reliability and 66% had population-specific validity. A majority of the studies used self-reported measures, even though many had little evidence of validity and reliability. The researchers of the systematic review suggested that future researchers should use valid and reliable measures of physical activity with well-established evidence of psychometric properties, for instance, hip accelerometers and the Community Health Activities Model Program for Seniors Physical Activity Questionnaire for older adults. With the advance in modern technology, access to technology for measuring physical activity, such as accelerometers and pedometers, is easier than ever, so future researchers sh ld take the opportunity to improve the quality of their studies by using better measurement tools. [27] On the other hand, it is important to note that most of the questionnaires were not developed for use in individual or group iterventions, but for population surveillance. In some cases, the tools may not have been sensitive enough to measure the outcome. Furthermore, none of the tools can adequately deta ect change in physical activity over time, but capture more of a snapshot of a particular period of time.[28]

For Low Back Pain[edit | edit source]

Other Outcome Measures[edit | edit source]

Body Mass Index (BMI), physiological measures, and quality of life are frequently used as secondary outcome measures for physical activity. However, these outcome measures should only be used if they are relevant to the aims ofand the study other researcherinterestsest.

Cycle of Physical Inactivity Causing Low Back Pain[edit | edit source]


Bone Strength and Disc[edit | edit source]

Picture to show normal and osteoporotic bone

Bone health is also likely to be affected in an inactive population. According to Wolff’s Law, if the loading on a bone decreases, the bone will become less dense and weaker due to the lack of the stimulus required for continued remodeling and increased resorption from osteoclasts.[31] Physical activity can influence bone mass by causing compressive or bending loads on bone. The bone formation will then be the resultant response from the strain/temporary deformation which will trigger primary and secondary responses in bone.[32] As such, being physically inactive may put one more at risk of having a low bone mineral density and consequently developing osteoporosis. However, current evidence still lacks high-quality studies to confirm the inverse relationship between back pain and bone health.[33][34]

A 2015 study demonstrated a 'dose-response relationship' between physical inactivity, including narrow intervertebral disc height. Intervertebral disc narrowing is a feature of degenerative disc disease, suggested by some to be the single most important structural risk factor for low back pain.[35]

Musculoskeletal[edit | edit source]

Evidence suggests that in response to physical inactivity, skeletal muscles go through a process called adaptive reductive remodeling.[32] This results in a loss of muscle mass (atrophy) and changes in muscle composition. Muscle atrophy is characterized by a general reduction in muscle cfibresectional fiber area as well as a reduction in the overall number of mfibresfibers,[36] leading to a decrease in muscle strength. Studies have shown that paraspinal muscles atrophy and increase in fat content are associated with low back pain as the result of physical inactivity.[37][35]

An example of high fat (50%) content of multifidus

Back extensor muscles

Metabolism[edit | edit source]

Chronic LBP patients who are deconditioned, have their level of activity affected but also other parts of their body . For instance, metabolic factors including carbohydrate and lipid metabolism will become less efficient and effective than healthy non-chronic LBP individuals.[32]

As a reduced physical activity level will eventually lead to weight gain and a change in body composition, people with LBP are reported to have a higher body fat percentage compared to age- and gender-matched individuals.[38] Obesity has been shown to have the strongest association with seeking care for low back pain.[39]

Factors Affecting Adults Participation in Physical Activity[edit | edit source]

Occupation[edit | edit source]

A person with a job that requires a relatively high demand for physical activity can be sedentary in his leisure time. However, although the physical activity guideline is met he/she may still be considered sedentary but physically active. On the other hand, a person with a sedentary job can be very active in his/her leisure time, and his/her physical activity may meet thuideline and he will not be classified as physically inactive. The type of occupation could affect the amount of physical activity, but it doesn’t necessarily have a direct influence on the physical activity one does during leisure time.

Original5 f1.jpg

The above figure demonstrates time trends for the prevalence of leisure time physical activity (LTPA) and work-related physical activity (WRPA). Values are from the Spanish National Health Interview Survey and are expressed as percentages.

Type of occupation[edit | edit source]

International research indicates that blue-collar employees typically exhibit lower rates of leisure-time physical activity. While “lack of time” and “work demands” are commonly reported barriers to activity, a secondary analysis of cross-sectional data from the Australian Health Survey found out among the three categories of occupations (professional, white-collar, and blue-collar), individuals in blue-collar occupations were approximately 50% more likely to be classified as insufficiently active.[40]

Another systematic review found that white-collar/professionals demonstrated the highest leisure-time physical activity compared to blue-collar workers and concluded that there is convincing evidence that those employed in occupations demanding long work hours and low occupational physical activity are at risk of inactivity.[41] From both studies, they showed that there is an association between physical inactivity and type of occupation.


Job Position, Job Stres,s and PsychologicMany factors can[edit | edit source]

There are many factors that can affect a person’s physical activity. A cross-sectional study by Martins and Lopes (2013) investigated the association of rank (position of the job in an office setting), job stress, and psychological distress with physical activity in a military setting. The results showed that lower rank (‘high effort and low reward’) was associated with more occupational physical activity, more job stress, and with less physical activity in sports/physical exercise in leisure, and that psychological distress was associated with less physical activity in sports/exercise in leisure.[42]

Environment[edit | edit source]

The physical environment has a consistent association with physical activity bbehavior One review showed that accessibility, opportunities, and aesthetic attributes had significant associations with physical activity. Weather and safety showed less-strong relationships.[43] However, it is hard to isolate one factor from others, other variables affecting physical activity behaviour, and whether the changes are caused by the factor that the researcher is interested in is unknown. A better research model and measurement strategies is needed for future research.

Other Factors[edit | edit source]

  • Personal factors
    • enjoyment of exercise
    • expectation of benefits
    • intention to exercise
    • self-efficacy
    • self-motivation
    • social support from friends/peers/spouse/family
    • lack of time
  • Race/ethnicity
  • Social class etc.[44]

Evidence For[edit | edit source]

A Dutch cross-sectional study from 2009[45] investigated the U-shaped relationship between physical activity and low back pain. The study concluded that both extremes of physical activity, excess activity or insufficient activity, associated with a high risk of LBP. An increased prevalence in LBP was also found in inactive participants with sedentary behavior. In addition, there is a potential gender-related risk for LBP in inactivity because the result is more significant in women compared to men.

U Shaped model demonstrating intensity of activity and risk of back pain

Another cross-sectional study from 2015[35] explored the association between physical inactivity and intervertebral disc height, spinal muscles, fat content and low back pain, and disability. Results concluded that participants with lower activity levels had higher BMI, narrower intervertethe bral disc height, higher fat content of multifidus,and increased risk of high-intensity pain/disability ratio after adjustment for age, gender and BMI. Further details are explained in the following table.

Table to show findings from Teichtahl, et. al., 2015

Evidence Against[edit | edit source]

A systematic review written in 2011 reviewed 7 studies to look at if patients with chronic low back pain have an altered level and/or pattern of physical activity compared to healthy individuals. The gathered data revealed no significant difference in the overall activity level of adults (18-65 y/o) or adolescents (<18y/o) with chronic low back pain; however, there is evidence that older adults (>65 y/o) with chronic low back pain are less active than controls. They concluded that there is no conclusive evidence that patients with chronic low back pain are less active than healthy individuals and there is a lack of studies in this area.[46]

Analysis for Sitthipornvorakul, 2011[47]

Limitations[edit | edit source]

The current literature looking at physical inactivity causing LBP are mainly cross-sectional studies. However, physical activity is continuous and patterns could change. Therefore, future longitudinal studies will help to better identify this cause and effect relationship.[48]

Furthermore, pain is complex and difficult to measure due to its subjective nature and it being a multidimensional experience. There is no external reference or gold standard.[49]

Physical activity is generally measured using self-reported questionnaires, which can lead to overestimation or underestimation. People generally tend to overestimate physical activity and underestimate sedentary behavior[50], which reflects the reliability and validity of questionnaires. A more sensitive alternative to questionnaires would be to use objective instruments such as pedometers, accelerometers, or heart rate monitors.

Interviews[edit | edit source]

An interview with Grahame Pope, the Head of Physiothe therapy Education at University of Nottingham

An interview with Eric Bandoo, a band 6 Physiotherapist at Nottingham Citycare trust

References[edit | edit source]

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