How to Tell If Your Workout Intensity Is Right

This article is informational only and is not medical advice. Talk to a doctor before starting a new exercise program, especially if you have an existing health condition.

A common problem for beginners is not knowing whether a workout actually counted as "moderate" or "vigorous" intensity, terms that show up constantly in exercise guidelines but rarely get explained with a simple test you can use mid-workout. The CDC outlines three practical ways to judge this: the talk test, a 0 to 10 effort scale, and target heart rate.

The talk test

The simplest method requires no equipment at all. According to the CDC, during moderate-intensity activity, you should be able to talk but not sing. During vigorous-intensity activity, you should not be able to say more than a few words without pausing for a breath.

This matters practically because the CDC's adult activity guidelines are built around these two intensity categories: 150 minutes of moderate-intensity activity per week, or 75 minutes of vigorous-intensity activity, or some equivalent combination of the two. If you're not sure which category your workout falls into, the talk test gives you an immediate, no-equipment way to check mid-session.

Examples the CDC lists as typically moderate-intensity include walking briskly at 2.5 miles per hour or faster, recreational swimming, bicycling slower than 10 miles per hour on level terrain, and general yard work. Vigorous-intensity examples include jogging or running, swimming laps, bicycling faster than 10 miles per hour, and jumping rope.

The 0 to 10 effort scale

The CDC also describes a relative intensity scale from 0 to 10, where 0 represents the effort of sitting completely still and 10 represents maximal effort. On this scale, moderate-intensity activity corresponds to a 5 or 6, while vigorous-intensity activity starts at a 7 or 8.

This scale is useful because it accounts for relative fitness. The CDC specifically notes that an activity that feels vigorous for someone of average fitness might only feel moderate to someone who is very fit. Because of this, the same activity, say, a jog at a certain pace, can land at different points on two different people's 0 to 10 scale, even though the actual pace is identical.

Target heart rate: a more precise option

If you want a numerical check rather than a subjective feeling, the CDC describes target heart rate zones based on your estimated maximum heart rate.

The estimate is calculated as 220 minus your age. For moderate-intensity activity, your target heart rate should fall between 50 percent and 70 percent of that estimated maximum. For vigorous-intensity activity, the target range is 70 percent to 85 percent of the estimated maximum.

As a worked example using the CDC's own method: for a 50-year-old person, the estimated maximum heart rate is 220 minus 50, which equals 170 beats per minute. The moderate-intensity zone would be 170 times 0.50, or 85 beats per minute, up to 170 times 0.70, or 119 beats per minute. So a 50-year-old doing moderate-intensity exercise should see a heart rate somewhere between 85 and 119 beats per minute during the activity.

For a 35-year-old, the estimated maximum is 220 minus 35, or 185 beats per minute. The vigorous-intensity zone is 185 times 0.70, or about 130 beats per minute, up to 185 times 0.85, or about 157 beats per minute.

To check your own pulse manually, the CDC suggests taking it at your wrist, using your index and middle fingers (not your thumb) over the radial artery, and counting beats for a full 60 seconds, or counting for 30 seconds and doubling the result.

Why this matters for beginners specifically

If you're new to exercise, it's easy to either undertrain, staying so far below moderate intensity that you're not meeting the weekly guideline, or overtrain, pushing into vigorous intensity sooner than your body is ready for, which raises both the discomfort and the dropout risk. Having at least one objective check, whether that's the talk test, the 0 to 10 scale, or a heart rate check, helps you calibrate your effort more accurately than guessing based on how tired you feel, especially in the first few weeks before your sense of exertion has adjusted.

Putting the three methods together

You don't need to use all three every time. A practical approach:

• Use the talk test for a quick, no-equipment check during almost any activity.
• Use the 0 to 10 scale when you want a slightly more graded sense of effort, useful for comparing one workout to another over time.
• Use target heart rate when you want a specific number to aim for, particularly useful if you're using a fitness tracker or watch that displays real-time heart rate.

Key takeaways

• The talk test is the simplest check: moderate intensity allows talking but not singing, vigorous intensity limits you to a few words at a time.
• The CDC's 0 to 10 relative effort scale places moderate intensity at 5 to 6 and vigorous intensity at 7 to 8.
• Target heart rate zones are calculated from an estimated maximum heart rate of 220 minus your age, with moderate intensity at 50 to 70 percent of that number and vigorous intensity at 70 to 85 percent.
• These three methods are different ways to measure the same two intensity categories used in CDC's weekly activity guidelines.
• Checking intensity directly helps beginners avoid both undertraining and overtraining in the early weeks of a new routine.

Always consult a doctor before beginning a new exercise routine, particularly if you have a pre-existing health condition.