UK CMOs: When it comes to physical activity some is good, but more is better

New guidelines demonstrate the comprehensive benefits of any physical activity for anyone, say the UK’s Chief Medical Officers

Physical activity is an under appreciated asset in our clinical arsenal. This is despite renowned epidemiologist Jerry Morris describing physical activity as a “best buy” for public health as far back as 1994. [1] Today, barely a week goes by without a new piece of evidence on the contribution of physical activity to health, happiness, and longevity. [2]

Exercise is one of the cheapest and most effective forms of medicine. [3]

It is our role as Chief Medical Officers (CMOs) of the four home countries to describe what the evidence shows on health enhancing behaviours and design clear, evidence-based, guidelines for use by health professionals, policy makers, and the public. [4]  

In 2011, the first ever UK-wide CMO Physical Activity Guidelines were published, outlining the recommendations for achieving optimal health benefits across four groups; from the early years, to older adults. [5] 

As a nation however, we are insufficiently active for maximal health benefits to be seen. [6] One in four people have said they would be more active if advised by either a GP or nurse, yet health professionals’ awareness of national guidelines appears low. [7,8] 

UK CMO Physical Activity Guidelines 2019

Today, we launch the updated UK CMO Physical Activity Guidelines, 2019 and accompanying infographics. [9]

New evidence is drawn upon to provide updated guidelines across four age groups and for the first time additional guidance is provided for being active during pregnancy and after birth, and for disabled adults. The guidelines present thresholds for the achievement of optimal health benefits, recognising that benefits are achieved both above and below guideline levels. 

The evidence base is clear; some physical activity is good, but more is better. The multitude of benefits can start to occur at even the lowest levels of activity, and therefore all individuals should be encouraged to do what they can. 

This new guidance gives us all an opportunity to harness the positive opportunities of physical activity. 

Early years

All children aged under five should be active every day and participate in a range of activities including outdoor play. The wider range of physical capabilities are considered in three distinct developmental stages: infants (less than 1 year); toddlers (1-2 years); and preschoolers (3-4 years). Once children are mobile, the evidence supports a guideline level of at least 180 minutes a day for optimal health benefits. 

Children and young people

Childhood and adolescence are critical development stages for physical activity. Children and young people should be active every day. The evidence supports a threshold of an average of 60 minutes moderate-to-vigorous activity per day across the week. A variety of types and intensities of activity are recommended including those which develop movement skills, muscular fitness, muscle and bone strength.  


The evidence continues to support optimal health benefits in adults from being physically active every day, working to achieve a minimum of 150 minutes of moderate intensity physical activity, or 75 minutes of vigorous intensity physical activity per week.

Emerging evidence supports the health benefits of high intensity interval training activities (HIIT), which are, for the first time included in the guidelines. [10] Furthermore, the guidelines underline the importance of including strength-based activities on at least two days of the week. 

In 2018, a review of the evidence acknowledged the wealth of health benefits for activity during pregnancy, and after giving birth. [11] Women are encouraged to also achieve 150 minutes of physical activity per week, continuing with usual activity if already active or safely increasing activity if currently inactive. 

A review of the evidence established various benefits of regular physical activity for disabled adults, and importantly no evidence was found that participation in appropriate activity increased the risk of injury or harm. [12] Disabled adults are encouraged to achieve 150 minutes of moderate intensity activity per week, including strength and balance activities on at least 2 days per week. 

Older adults  

The importance of regular strength, flexibility and balance activity becomes even more important with age, helping to maintain physical function, reduce the risk of falls and delay the decline in muscle mass. [13]

Guidelines for older adults encourage daily activity and 150 weekly minutes of moderate intensity activity for optimal health gains. However, the benefits of even light intensity activity are recognised and activities to improve strength, balance and flexibility are recommended on at least two days of the week. It is emphasised that these sessions can be incorporated into other types of activities, rather than necessarily being in addition. 

Sedentary behaviour

Despite notable developments in the evidence base for the harmful effects of sedentary behaviour there is not yet enough evidence to set a threshold level. [1] Instead the UK CMO guidelines emphasise the importance of minimising time spent sedentary for all age groups. 


When it comes to physical activity some is good, but more is better. The benefits to health are far reaching and physical activity remains an underutilised tool for clinicians. We welcome the work across the UK to support physical activity such as the Moving Medicine initiative that is tackling this challenge. We anticipate our new 2019 guidelines being embedded in this work. 

These guidelines and accompanying infographics are designed to increase awareness and make it easier for health professionals and others to promote the benefits of physical activity to all. Please use them and help us to spread the word.

Catherine Falconer is the Specialty Registrar in Public Health, Department of Health and Social Care

Charlie Foster is the UK Chief Medical Officers Expert, Committee for Physical Activity, University of Bristol

Catherine Calderwood is the Chief Medical Officer for Scotland 

Michael McBride is the Chief Medical Officer for Northern Ireland

Frank Atherton is the Chief Medical Officer for Wales

Sally Davies is the Chief Medical Officer for England


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  2. Ekelund, U; Tarp, J; Steene-Johannessen, J, et al. 2019. Dose-response associations between accelerometry measured physical activity and sedentary time and all cause mortality; systematic review and harmonised meta-analysis. BMJ; 366; I4570.
  3. Pedersen BK, Saltin B.  Exercise as medicine—evidence for prescribing exercise as therapy in 26 different chronic diseases. Scand J Med Sci Sports 2015;25(Suppl 3):1–72.
  4. UK Chief Medical Officers’ Low Risk Drinking Guidelines. 2016.
  5.  Department of Health, Physical Activity, Health Improvement and Protection. Start Active, Stay Active: A report on physical activity from the four home countries’ Chief Medical Officers. London: Department of Health; 2011.
  6. Public Health Outcomes Framework. Physical Activity Profiles.
  7. Orrow G, Kinmouth AL, Sanderson S, Sutton S. Effectiveness of physical activity promotion based in primary care; systematic review and meta-analysis of randomised controlled trials. BMJ 2012; 344; e1389.
  8. Chatterjee, R; Chapman, T; Brannan, M, and Varney, J. GPs’ knowledge, use, and confidence in national physical activity and health guidelines and tools: a questionnaire-based survey of general practice in England. Br J Gen Pract 2017 Oct;67(663):e668-e675.
  9. UK Chief Medical Officers’ Guidelines on Physical Activity. 2019.
  10. Batacan RB, Jr., Duncan MJ, Dalbo VJ, Tucker PS, Fenning AS. Effects of high-intensity interval training on cardiometabolic health; a systematic review and meta-analysis of intervention studies. Br J Sports Med. 2017; 51(6):494-503. 
  11. Smith, R; Shakespeare J; Williams, Z; Knight, M; and Foster, C. Physical activity for pregnant women; an infographic for healthcare professionals. Brit J Gen Pract. 2017; 67(663). 
  12. Public Health England. Physical activity for general health benefits in disabled adults; Summary of a rapid evidence review for the UK Chief Medical Officers’ update of the physical activity guidelines. London; 2018. 
  13. Skelton DA and Mavroedi, A. How do muscle and bone strengthening and balance activities (MBSBA) vary across the life course, and are there particular ages where MBSBA are most important?. Journal of Frailty, Sarcopenia and Falls. 2018;3(2):74-84.