REF-1566 · Bull et al., 2020 · British Journal of Sports Medicine · Paper · PubMed

How much activity for health?

WHO: 150-300 min moderate or 75-150 min vigorous a week, strength on 2+ days, and from 65 balance-and-strength on 3+ days. Public-health guidance, consensus, not written for athletes.

Main caveat: Evidence base: much of it observational and self-reported, with thin data from low-income settings and for many subgroups.
very strong evidenceMeasured on non-athletes and recreational people

WHO updated its 2010 advice using reviews behind other national guidelines, updated from 2017 to September 2019, with new umbrella reviews for gaps. New points: a weekly range rather than a minimum, no 10-minute bout requirement, multicomponent training for all older adults rather than only those with poor mobility, and a first recommendation on sedentary time.

Statements that activity confers benefits for mortality and diabetes are the guideline's wording; the supporting literature for many of them is cohort data.

Protocol

Panel: experts, policy makers and end users, reaching consensus without voting; seven external reviewers and an online consultation with over 400 contributions.
Grading: GRADE for certainty; recommendations strong or conditional. All-cause and cardiovascular mortality were ranked most critical.
Funding: Public Health Agency of Canada and the Government of Norway; competing interests none declared.
Independence: Ekelund, Garcia and Dempsey are also authors of dose-response work in the base (REF-1569, REF-1567).

Key Results

GroupRecommendationStrength
Adults 18-64, aerobic150-300 min moderate, 75-150 min vigorous, or equivalent mix, weeklystrong
Adults, strengthmoderate or greater, all major muscle groups, 2 or more daysstrong
Adults, above the rangemore than 300 min moderate or 150 min vigorous for additional benefitconditional
Adults, sedentary timelimit it; replace with activity of any intensitystrong; no threshold set
65 and overas adults, plus varied multicomponent balance and strength on 3 or more daysstrong
Ages 5-17an average of 60 min/day, mostly aerobic; vigorous and strengthening work at least 3 daysstrong
Pregnancy and postpartumat least 150 min moderate; aerobic and strengtheningstrong
Dose shape: moderate-certainty curvilinear association for some outcomes. Below-guideline amounts also bring benefit, and the panel found no evidence for a dose-response with more strength volume.
Clearance: generally unnecessary before light or moderate activity for people without contraindications.
Falls: high-certainty evidence that balance and functional exercises lower fall rates in older adults.
Cognition: the guideline lists cognitive health among the outcomes for adults; the umbrella review in REF-1580 disputes how firm that is in healthy people.
Internal tension: the paper says it is not possible to specify where diminishing returns begin, yet explains the range as capturing maximal risk reduction with little beyond it, and adds a conditional recommendation for more. Treat the top of the range as a judgment.
Wording: the summary table states the adult range with the words at least in front of it, a floor written as a range. The abstract omits those words.

Mechanisms

Measured: nothing new; a synthesis.
Inference: the same aerobic numbers come from cohorts where most people do little. They mark where a population's gain is largest, not where an athlete's training should stop.

Practical Application

How much activity for health? WHO: 150-300 min moderate or 75-150 min vigorous a week, strength on 2+ days, and from 65 balance-and-strength on 3+ days. Public-health guidance, consensus, not written for athletes.
Good for: a floor for someone with no race, and a reminder that strength and, later, balance belong in it.
Good for: starting small. Some is better than none, any bout length counts, and increases should be gradual.
Not good for: performance doses or a safe maximum for athletes; both are outside its scope.
Not good for: a sitting limit in hours; none could be set.

Limitations

Evidence base: much of it observational and self-reported, with thin data from low-income settings and for many subgroups.
Extrapolation: recommendations for disability, and sedentary advice for pregnancy and chronic conditions, were extrapolated from general populations and downgraded.
Type and domain: evidence was insufficient to say whether benefits vary by type or domain of activity.
Athletes are outside the scope, and harms at training volumes are not addressed.
How this entry was checked and changed
Why this level

governing-body consensus built on systematic reviews. This grades the process. The panel's own certainty for adult aerobic and strength volume is moderate, and much of that evidence is observational, so A+ does not make the dose causal