The Australian government recommends at least 150 minutes per week of moderate-intensity exercise, or at least 75 minutes per week of high-intensity exercise.
Which is great on paper — but what do those intensities actually mean in the real world?
Physical activity can broadly be split into three categories: low-intensity, moderate-intensity, and high intensity. (And zero intensity, if you count “browsing Netflix with the remote control in one hand while reaching for more popcorn with the other” as physical activity.)
Here’s the easy way to tell which intensity you’re moving at.
Examples include a casual walk, a stretch session, a beginners’ yoga class or tai chi, bike riding or using a cross trainer (aka an elliptical) at an easy pace. Incidental exercise — everyday movements like bringing in the shopping, walking upstairs or doing housework, which burns a surprising number of calories — also counts as low-intensity activity.
To understand exercise intensity it’s helpful to know your maximum heart rate (MHR), which you can estimate by subtracting your age from 220 — so a 35-year-old has a MHR of about 185 beats per minute, for example.
Low-intensity activity is that which gets you to about 40 to 50 percent of your MHR.
A heart-rate monitor is obviously the best way to monitor your heart rate: a fitness band on your wrist will give you a decent estimate, though a chest strap is most accurate. You can get an idea of your heart rate without any equipment by taking your pulse for 15 seconds, counting the number of beats, then multiplying that number by four.
Of course, measuring your heart rate is pretty technical — and not really that practical to do while you’re exercising. So the easiest on-the-go way to check your exercise intensity is the talk test: if you can talk and sing while exercising without running out of breath, you’re exercising at a low intensity.
While it’s true that low-intensity exercise like walking isn’t the most effective way to lose weight in the long term, that definitely doesn’t mean it’s a waste of time: incidental movement is linked to improved overall physical fitness and health.
Moderate intensity is what most of us would think of as a proper workout. Many of the low-intensity exercises listed above can easily become moderate-intensity exercises by upping your pace: brisk walking or walking uphill, or a strenuous yoga session, for example.
Moderate-intensity exercise can also include weight training, or endurance exercise — things like jogging, cycling, or lap swimming. If you have older (and therefore heavier) children, carrying them around also falls in the moderate intensity category.
During moderate-intensity exercise, you’re at 50 to 70 percent of your MHR. To go by the talk test, you can comfortably chat, but you can’t sing any more than a few words without running out of breath.
Ideally, you want to accumulate 150 minutes of moderate-intensity exercise every week.
If moderate-intensity exercise is all you can tolerate but you worry it’s not going to have maximum impact, never fear: recent research indicates moderate intensity can deliver the same health benefits as high-intensity workouts. (The only downside is that you have to work out at a moderate pace longer.)
Examples include circuit training, vigorous forms of weight training, and moderate-intensity exercises at a heart-pounding pace — sprints in the park or up the length of the pool, for example.
Your MHR during a high-intensity (aka vigorous-intensity) workout is 70 to 85 percent, and to go by the talk test, you can’t say any more than a few words without having to pause to breathe. (Emotionally, you might be praying for a swift and merciful death.)
Note that just because you’re dripping with sweat doesn’t necessarily mean you’re exercising at high intensity — a bunch of other factors can influence sweating, including your workout environment, your fitness level, and your gender.
Seventy-five minutes of high-intensity training is recommended per week.
High-intensity exercise is super popular right now in the form of high-intensity interval training (aka HIIT), where you work out at a high intensity for a set period of time, take a short break to get your heart rate back down a little, then repeat. HIIT is particularly effective for weight loss and increasing cardiovascular fitness.
The big advantage of high-intensity exercise is that you get big health benefits from less time spent exercising — even though you have to put in more effort, it’s over faster. And while that increased effort is notorious for bringing on that “I wish I was dead” feeling, studies suggest that many fitness beginners actually prefer HIIT workouts.