World Health Organization 2020 guidelines on physical activity and sedentary behaviour

The final recommendations on physical activity and sedentary behaviour for each population group are summarised in table 4. For all populations, doing some physical activity is better than doing none. If individuals are not currently meeting these recommendations, doing some physical activity will bring benefits to health. Individuals should start with small amounts of physical activity and gradually increase frequency, intensity and duration over time. The GDG concluded that the benefits of doing physical activity and limiting sedentary behaviour outweighed the potential harms. Any potential harms may be managed by a gradual increase in the amount and intensity of physical activity.

Pre-exercise medical clearance is generally unnecessary. Individuals who are not currently regularly active and have no contraindications can be recommended to commence and gradually increase levels and intensity of physical activity without a medical clearance. An individual who is habitually engaging in moderate-intensity activity can gradually increase to vigorous intensity activity without needing to consult a healthcare provider. Those who develop new symptoms when increasing their levels of activity should consult a healthcare provider. These guidelines are for the general population and do not address the benefits and harms experienced by athletes undertaking the types and amounts of activity necessary to improve performance-related fitness for participation in competition.

The evidence supporting each of the updated or new recommendations is summarised for each group. Further details, including a more detailed narrative summary of evidence and the evidence profile tables summarising the evidence used for all recommendations, are available from WHO.

Recommendations for children and adolescents (5–17 years)

The evidence affirmed that physical activity in children and adolescents is associated with improved physical, mental and cognitive health outcomes. Many of the benefits of physical activity are observed with an average of 60 min of moderate-to-vigorous physical activity (MVPA) daily, although physical activity beyond 60 min of MVPA daily provide additional health benefits. There was insufficient evidence to determine whether specific health benefits vary by type or domain of physical activity. The evidence showed clearly that increased time in aerobic MVPA increases cardiorespiratory fitness and that increased muscle-strengthening activities increases muscular fitness, with some evidence showing incremental benefits of doing both. One notable update from the 2010 guidelines was evidence to support changing from ‘at least’ 60 min to ‘an average of’ 60 min of MVPA per day as this was deemed to more closely reflect the body of evidence and the way MVPA has been measured. The physical activity recommendation was rated as strong based on overall moderate certainty evidence. The evidence indicated that greater time spent in sedentary behaviour is related to adverse health outcomes. The association between sedentary behaviour and adverse health outcomes is generally stronger for television viewing or recreational screen time as the specific exposure variable than for total sedentary time in youth. There was, however, insufficient evidence to set a precise threshold (or ‘cut-off’) for the amount of sedentary or recreational screen time. The sedentary behaviour recommendation was rated as strong based on low certainty evidence.

Recommendations for adults (18–64 years)

The evidence reaffirms that all adults should regularly undertake physical activity and that some physical activity is better than none. The adult guidelines include strong recommendations based on overall moderate-certainty evidence on weekly volumes of aerobic and muscle-strengthening physical activity. Many of the benefits of physical activity are observed within average weekly volumes of 150–300 min of moderate intensity or 75–150 min of vigorous intensity, or an equivalent combination of MVPA. The weekly range of recommended aerobic activity volume is a notable difference compared with the 2010 WHO recommendations that only specified minimum weekly thresholds. MVPA bouts of any duration now count towards these recommendations, reflecting new evidence to support the value of total physical activity volume, regardless of bout length. This recommendation differs from the requirement of bouts of at least 10 min in the previous WHO 2010 guidelines.

There is moderate-certainty evidence of a curvilinear dose-response association between physical activity volume and some health outcomes, such as all-cause and cardiovascular disease (CVD) mortality, and incident cancer and diabetes. Health benefits occur with levels of physical activity below the recommendations, supporting the statement that some physical activity is better than none. More physical activity is better, although the relative benefits tend to diminish at higher levels of physical activity. However, it is not possible to specify the physical activity levels where diminishing returns begin. For this reason, the new recommendation that aerobic physical activity volumes higher than 300 min of moderate-intensity activity per week, or 150 min of vigorous-intensity activity per week have additional health benefits, is rated as conditional. Beyond aerobic physical activity, additional health benefits will occur through participation in muscle-strengthening activities at moderate or greater intensity on 2 or more days a week, a strong recommendation supported by moderate-certainty evidence. There was no evidence to support a dose-response association with higher volumes of muscle-strengthening activities.

There was insufficient evidence to determine whether specific health benefits vary by type or domain of physical activity. Physical activity accrued at work, leisure, home or during transportation count towards the recommended amounts.

The reviewed evidence on sedentary behaviour and health outcomes in adults provided support that all adults should limit the amount of time spent sedentary. There was moderate-certainty evidence that the relationship of sedentary behaviour with all-cause and CVD mortality varies by amount of physical activity. For other outcomes, the evidence was insufficient. New evidence on the interdependent relationship between sedentary behaviour and physical activity underpinned the additional guidance that recommends increased levels of MVPA in the context of high levels of sedentary time. However, there was insufficient evidence to specify quantitative thresholds of sedentary behaviour, to determine whether specific health benefits vary by type or domain of sedentary behaviour or to determine the influence of frequency and duration of breaks in sedentary behaviour on health outcomes.

Recommendations for older adults (65 years and above)

The evidence reviewed on physical activity and sedentary behaviour for adults also applied to older adults for the common set of critical health outcomes (table 3), because the majority of studies employed no upper age limit and therefore included adults over the age of 65 years. Additional health-related outcomes were reviewed because of their significant importance to older adults: 1) falls; 2) fall-related injuries; 3) physical function; 4) frailty and 5) osteoporosis.

New high-certainty evidence demonstrates an inverse dose-response relationship between volume of aerobic physical activity and risk of physical functional limitations in older adults. High-certainty evidence demonstrates that balance and functional exercises reduce the rate of falls and that engaging in a range of different types of physical activity can help to improve a wide range of elements of physical function. Moderate-certainty evidence indicates that the risk of fall-related injury may be reduced with multicomponent physical activity (combinations of balance, strength, endurance, gait and physical function training). As such it is recommended that as part of their weekly physical activity, older adults should do varied multicomponent physical activity at moderate or greater intensity on 3 or more days a week in order to enhance functional capacity and prevent falls. One notable update from the previous 2010 guidelines is that regular participation in this type of physical activity is recommended for all older adults rather than specifically those with poor mobility. Moderate-certainty evidence indicates that programmes involving multiple exercise types probably have significant effects on bone health and osteoporosis prevention. Because the evidence reviewed for sedentary behaviour in adults included those over the age of 65 years, the adult recommendations were deemed to also apply for this population group.

Recommendations for pregnant and postpartum women

There is high-certainty evidence that physical activity during pregnancy is associated with reduced gestational weight gain and reduced risk of gestational diabetes mellitus in pregnant women with overweight or obesity. There is high-certainty to moderate-certainty evidence that the incidence of gestational hypertension is no different between pregnant women who exercise and those receiving standard antenatal care.

Among pregnant women with overweight or obesity, there is low-certainty to moderate-certainty evidence to suggest no increased risk of low birth weight, small for gestational age or large for gestational age babies between women who are physically active and those in standard antenatal care. There is moderate-certainty evidence of a small, but significant, reduced risk of preterm birth in mothers who engaged in vigorous physical activity. Similarly, among pregnant women with overweight or obesity there was no significant difference in the risk of preterm birth between those who were physically active and those in standard antenatal care. Available evidence from intervention trials combining both aerobic and muscle-strengthening physical activity support the recommendation for regular strength training to be included for pregnant and postpartum women.

No direct evidence was reviewed on sedentary behaviour for this subpopulation; however, the GDG reviewed the evidence for general populations and concluded it was applicable. Therefore, the sedentary behaviour recommendations for adults are extrapolated to pregnant and postpartum women and the certainty of the evidence downgraded for indirectness.

Recommendations for people living with chronic conditions

Physical activity is considered safe for adults living with the selected chronic conditions without contraindications, and the benefits generally outweigh the risks. Evidence was reviewed for the following chronic conditions: cancer, hypertension, type 2 diabetes and HIV. Greater physical activity is related to improved health outcomes in people living with coronary heart disease. Among adults with type 2 diabetes, there is high-certainty evidence that physical activity is associated with decreased risk of CVD mortality and decreased levels of haemoglobin A1c, blood pressure, body mass index and lipids. Among adults with hypertension, there is high-certainty evidence that physical activity decreases risk of progression of cardiovascular disease and reduces blood pressure, while there is moderate-certainty evidence that physical activity reduces the risk of CVD mortality. High-certainty evidence shows that physical activity performed postcancer diagnosis is related to lower risks of mortality from all causes and mortality from cancer in female breast cancer survivors and colorectal cancer survivors.

Given that large numbers of people are currently living with HIV and that antiretroviral therapy has become effective and widely available, HIV is now considered a chronic condition. Thus, evidence on people living with HIV are included in these guidelines for the first time. There was moderate-certainty evidence that in people living with HIV, physical activity enhances health-related quality of life, maximal oxygen consumption, exercise tolerance, general health and physical functioning. There was moderate-certainty to high-certainty evidence that regular physical activity did not result in significant change in viral load, CD4+ count or disease progression, and as such, persons living with HIV are not adversely affected by physical activity.

There was moderate-certainty to high-certainty evidence that physical activity decreased symptoms of anxiety and depression. In addition, there was moderate-certainty to high-certainty evidence that physical activity was associated with a reduction in body fat percentage and an increase in lean body mass, but not waist circumference or body mass index.

Although there was no direct evidence on sedentary behaviour for these subpopulations, the GDG considered and concluded that the evidence for general populations was applicable. Therefore, the sedentary behaviour recommendations for adults were extrapolated to adults living with these chronic diseases and the certainty of the evidence downgraded for indirectness.

Recommendations for people living with disability

Evidence was reviewed for the following health conditions: multiple sclerosis, spinal cord injury, intellectual disability, Parkinson’s disease, stroke, major clinical depression, schizophrenia and attention deficit hyperactivity disorder (ADHD). The following health outcomes were examined: comorbidity, physical functioning, cognition and quality of life, but not all outcomes were assessed for each condition. This evidence was considered together with the evidence for those without disability and the resulting recommendations were extrapolated to be applicable to people with disability in general.

Physical activity is considered safe and beneficial for people living with disability without contraindications, and there are no major risks when it is appropriate to an individual’s current activity level, health status and physical functioning level. Adults living with disability may need to consult a healthcare professional or other physical activity and disability specialist to help determine the type and amount of activity appropriate for them.

In people with spinal cord injury, low-certainty and moderate-certainty evidence suggests physical activity reduces shoulder pain and improves vascular function in paralysed limbs. Insufficient evidence was available to determine the relationship between physical activity and comorbid conditions in individuals with intellectual disability or multiple sclerosis. There is high-certainty evidence showing that physical activity can improve functioning in people with multiple sclerosis, spinal cord injury and a history of stroke. For people with intellectual disability or Parkinson’s disease, this evidence is of low certainty and high certainty, respectively. Limited evidence was available for the relationship between physical activity and quality of life in people with multiple sclerosis, spinal cord injury and intellectual disability. However, for people with schizophrenia and major clinical depression there was moderate-certainty evidence for beneficial effects on quality of life. Moderate-certainty evidence indicates that physical activity can have beneficial effects on cognition in people with multiple sclerosis, Parkinson’s disease, a history of stroke, ADHD and major clinical depression. For people with schizophrenia this evidence was of high certainty.

The evidence on the associations between sedentary behaviour and health outcomes in children, adolescents and adults living with disability was derived from literature reviewed for the general populations. The GDG concluded that these recommendations could be extrapolated to children, adolescents, adults and older adults living with disability, according to their specific ability, but downgraded the certainty of the evidence due to indirectness. The GDG agreed that benefits accrued from reducing sedentary time and gradually increasing physical activity where possible, depending on ability. In the case of those living with disability, especially wheelchair users or those with low mobility, it is important to note that it is possible to avoid sedentary behaviour while sitting or lying by doing light-intensity or high-intensity activities that do not involve the lower extremities.