Moderate vs vigorous intensity

What's the difference between moderate and vigorous activity?

At moderate effort you breathe a bit harder and your heart rate rises slightly, but you can still hold a conversation⁵. At vigorous effort you breathe hard and fast, and you can't say more than a few words without pausing for breath².

This "talk test" needs no numbers or devices. If you can talk but not sing, you're at a moderate level^1,2.

Some examples:

• Moderate: brisk walking, playing volleyball, raking the yard².
• Vigorous: jogging or running, carrying heavy groceries, a strenuous fitness class².

Brisk walking, at moderate effort, is about 100 steps a minute or more for most adults, or roughly 2.5–3 mph (4–5 km/h) or faster. These are rough guides. The pace that's brisk for you depends on your height, age, fitness and any disability, which is why the talk test is a handy check.

Getting out of breath when you exercise is normal. Breathlessness that's much worse than the effort explains, or that comes with chest pain, is not.

Adults, including those aged 65 and over, should aim for at least 150 minutes of moderate activity a week, or at least 75 minutes of vigorous activity, or an equivalent mix. The WHO's ranges are 150–300 minutes of moderate and 75–150 minutes of vigorous activity. That's a minimum to aim for, and going beyond it is fine. The biggest gains come in the first 100 or so minutes a week, when you move from doing nothing to doing some, so doing less than the goal isn't wasted.

What are METs?

A MET is a way of rating how hard an activity is compared with resting. One MET is the energy you use sitting quietly, about 3.5 mL of oxygen per kg of body weight per minute⁶. Other activities are rated as multiples of that. Light activity such as shuffling, indoor walking or household chores is 1.6–2.9 METs⁹. Moderate is 3.0–5.9 METs and vigorous is 6.0 or more³.

MET-minutes add up different activities across a week. Multiply an activity's METs by the minutes you do it: 30 minutes at 6.0 METs is 180 MET-minutes³. The weekly amounts of moderate activity, vigorous activity or a mix work out at about 500–1000 MET-minutes a week^3,7.

If you like to count steps, adults aged 21–40 walking on a treadmill added about 1 MET for every extra 10 steps a minute: 110 steps a minute was about 4 METs and 120 about 5 METs⁸. Treat these as rough guides for older adults.

MET values are a starting point for choosing activities, not an exact measure of your own energy use³. Effort can feel different from the numbers.

You don't need to count METs. The talk test gives a similar answer without numbers.

When to check with a health professional

If you're starting exercise after a long break, it's always a good idea to see your doctor first.

Increase how hard and how long you go gradually. Serious problems are very rare when activity builds up slowly¹⁰. If you live with a long-term condition, build up slowly and ask your doctor or another health professional what suits you rather than relying on MET numbers. Aim for the same amounts as other adults where you can; if you can't, any activity you're able to do brings benefits.

For an injury or a health condition, see a health professional, such as your doctor or a physio.

Exercise doesn't have to hurt to work. Pain during exercise is a signal to stop or ease off. A sore muscle or joint, or some soreness a day or two later, is common when starting something new. Ease off, and see a doctor or other health professional if it persists or gets worse.

Call your local emergency number for chest pain or pressure (or pain spreading to the arm, neck, jaw or back, especially with sweating or feeling sick), severe breathlessness, fainting or collapse, signs of a stroke, a serious injury, or someone who isn't safe.