How much exercise per week: what the evidence asks of a busy adult

What the recommendation actually says

The World Health Organization sets a range, not a single number, and the range matters. The lower bound of 150 minutes is where most of the measurable benefit begins: lower risk of cardiovascular disease, type 2 diabetes, several cancers and depression. The upper bound of 300 minutes is not a ceiling. The guidelines state that going beyond it brings further health benefit, with no upper limit identified at which activity becomes harmful for a healthy adult.

Two details are often lost when the guideline is summarised.

• Strength counts separately. The two days of muscle-strengthening work are in addition to the aerobic minutes, and they should involve all major muscle groups.
• Sitting counts against you. The same document asks adults to limit sedentary time and to replace it with activity of any intensity. For a person who spends ten hours a day in a chair, this is the more demanding half of the recommendation. See sitting all day.

What counts as a minute

Any activity counts, in bouts of any length. Earlier guidelines required at least ten minutes at a time; the 2020 version dropped that condition. A fast walk from the car park, three flights of stairs taken quickly and a twenty-minute swim all go into the same total.

Intensity is judged by effort, not by the activity.

1. Light: you can sing. Strolling, standing, slow yoga. It does not count towards the 150 minutes, though it is better than sitting.
2. Moderate: you can talk in full sentences, but not sing. Your breathing is clearly faster.
3. Vigorous: a few words at a time. You could not keep it up for an hour.

A heart-rate monitor gives the same answer with more precision: see zone 2 training for the calculation.

The minimum that works in a full diary

People in demanding roles rarely lack motivation. They lack unclaimed hours. The arithmetic of the guideline is more forgiving than it looks.

• Three sessions of 40 minutes of moderate work reach 120 minutes. Add two brisk 15-minute walks and you are at 150.
• Two sessions of 25 minutes of vigorous intervals are worth 100 moderate minutes. One 50-minute moderate session on the weekend completes the week.
• Two strength sessions of 20 to 30 minutes cover the second recommendation. They can follow an aerobic session or stand alone.

That is about three hours a week, or under 2% of it. The calculator above adds up your own week and tells you where it stands against the range.

Why more than the minimum is worth considering

The relationship between activity and health is steepest at the bottom: going from nothing to 150 minutes brings the largest gain. But the curve keeps rising. A large study of more than 120,000 adults who underwent treadmill testing found that higher cardiorespiratory fitness was associated with lower long-term mortality at every level, including the very highest, with no plateau observed. Fitness of that kind is built by training beyond the minimum, and by including some hard work. See VO2 max.

For strength, the pattern is different. A pooled analysis of cohort studies found the lowest risk at around 30 to 60 minutes of muscle-strengthening activity per week, with no further reduction beyond. Two short sessions are therefore enough for health, even if more is needed to become notably stronger. See strength training for executives.

Common ways the week goes wrong

• Everything on Saturday. One long session is far better than none, but it leaves six days of sitting and a body that is never quite recovered or quite trained.
• Counting steps as training. Walking is valuable, and it is moderate activity only when it is brisk. Ten thousand slow steps around an office are light activity.
• No strength work at all. Runners and cyclists often meet the aerobic target three times over and skip the second recommendation entirely.
• Stopping when travelling. Two weeks of travel a month is half the year. A plan that only works at home is half a plan. See the hotel room workout.

Where a coach changes the result

The guideline tells you how much. It does not tell you what to do on a Tuesday when a board meeting has moved and you slept five hours. That judgement, repeated week after week, is what keeps the total above 150 minutes over a year rather than over a good month. It is also the reason the Club introduces each member to one coach who knows their schedule: see how entry works.

If you have a heart condition, high blood pressure or have not exercised for years, see a physician before starting vigorous work.