The honest answer: less than many people think to get real benefits, and more than most people currently do. The World Health Organization's 2020 guidelines are a useful reference, because they are based on a large body of research and are written for ordinary adults, not athletes.
What the guidelines say for adults
For adults aged 18 to 64, the WHO recommends:
- 150 to 300 minutes a week of moderate aerobic activity, or
- 75 to 150 minutes a week of vigorous aerobic activity, or an equivalent mix of both;
- muscle-strengthening activity on two or more days a week that works all major muscle groups;
- less sitting — replacing sitting time with any activity, even light, has benefits.
The guidelines also make a point that matters a lot for beginners: some activity is better than none. If you are doing nothing now, moving towards these numbers is worthwhile even if you do not reach them yet.
Older adults, pregnant people, and people with chronic conditions or disabilities have adapted recommendations. If that applies to you, check with your doctor.
Moderate vs. vigorous
A simple way to tell them apart is the talk test:
- Moderate — you can talk but not sing. Brisk walking, easy cycling, doubles tennis, active gardening.
- Vigorous — you can only say a few words before pausing for breath. Running, fast cycling, swimming laps, most interval training.
Roughly, one minute of vigorous activity counts as two minutes of moderate. That is why short, hard sessions like Tabata or intervals are popular with busy people.
What 150 minutes looks like
150 minutes sounds like a lot until you break it down:
- 30 minutes of brisk walking, 5 days a week; or
- 20 to 25 minutes every day; or
- three 25-minute interval sessions (vigorous, so they count double) plus two walks.
Activity can be split into shorter chunks across the day. A 10-minute walk after each meal adds up.
What counts as muscle strengthening
Anything that makes your muscles work harder than usual against resistance:
- bodyweight exercises such as squats, push-ups, lunges and planks;
- lifting weights, kettlebells or resistance bands;
- carrying heavy shopping, digging, climbing stairs with effort.
Two short sessions a week covering legs, hips, back, chest, shoulders, arms and core is enough to meet the guideline. The 4-week home plan does this.
A sample week for a beginner
- Monday — 20-minute bodyweight circuit (strength + moderate cardio)
- Tuesday — 30-minute brisk walk
- Wednesday — 20-minute bodyweight circuit
- Thursday — 30-minute walk
- Friday — rest or gentle stretching
- Saturday — 45-minute bike ride, hike or sport
- Sunday — rest or easy walk
That adds up to around 175 minutes, with two strength sessions — inside the guidelines.
Can you do too much?
Going above 300 minutes of moderate activity can bring additional benefits for many people, but the jump from doing nothing to doing something is where the biggest gains are. For beginners the main risk is not too much total exercise but too much too soon — which leads to injury and quitting. Build up over weeks, not days.
Start where you are
If 150 minutes feels far away, start with 10 minutes a day and add 5 minutes each week. Read how to start working out for a gentle first month.
Source: World Health Organization, Guidelines on physical activity and sedentary behaviour (2020). This article is general information, not medical advice.