Your target heart rate during exercise depends on your age and how intense you want your workout to be. For moderate exercise like brisk walking, aim for 50% to 70% of your maximum heart rate. For vigorous exercise like running or cycling hard, aim for 70% to 85%. A quick estimate of your maximum heart rate is 220 minus your age, which means a 40-year-old has a max of roughly 180 beats per minute and should stay between 90 and 153 bpm during most workouts.
How to Estimate Your Maximum Heart Rate
The most common formula is simple: subtract your age from 220. A 30-year-old gets a max of 190 bpm, a 50-year-old gets 170, and a 60-year-old gets 160. This formula, developed by Fox in the 1970s, remains widely used because it performs consistently across a broad range of people.
A newer formula, 208 minus 0.7 times your age, tends to be slightly more accurate on average. For a 30-year-old, it gives 187 bpm. For a 60-year-old, it gives 166. The difference between the two formulas is small for younger adults but grows with age, with the newer version generally producing a higher number for people over 40.
Neither formula is perfect. Research comparing multiple prediction equations found that all of them carry a typical error of about 7 to 10 beats per minute in either direction, with some individuals falling even further from the estimate. That means your true max could be 180 while the formula says 170, or vice versa. These formulas work well as starting points, but your body’s signals matter more than hitting an exact number.
Target Zones by Intensity
Once you have a rough maximum heart rate, you can calculate your target zones. Here’s what the ranges look like for three common ages:
- Age 30 (max ~190 bpm): moderate intensity is 95 to 133 bpm, vigorous intensity is 133 to 162 bpm
- Age 40 (max ~180 bpm): moderate intensity is 90 to 126 bpm, vigorous intensity is 126 to 153 bpm
- Age 50 (max ~170 bpm): moderate intensity is 85 to 119 bpm, vigorous intensity is 119 to 145 bpm
Moderate intensity covers activities like brisk walking, casual cycling, water aerobics, and doubles tennis. Vigorous intensity includes running, swimming laps, singles tennis, and hiking uphill. Most health guidelines recommend at least 150 minutes of moderate activity per week or 75 minutes of vigorous activity.
A More Personalized Calculation
The basic percentage-of-max method ignores one important variable: your resting heart rate. Someone with a resting rate of 55 bpm is starting from a very different baseline than someone at 80 bpm, even if they’re the same age. The Karvonen method accounts for this by using something called heart rate reserve, which is your maximum heart rate minus your resting heart rate.
To find your target with this method, multiply your heart rate reserve by the intensity percentage you want, then add your resting heart rate back. For example, a 40-year-old with a resting rate of 65 bpm has a heart rate reserve of 115 (180 minus 65). For moderate exercise at 60% intensity, that’s 115 times 0.60 plus 65, which equals 134 bpm. Typical training zones using this method range from 40% to 80% of heart rate reserve.
To get your resting heart rate, check your pulse first thing in the morning before getting out of bed. Count for 60 seconds on a few different days and average the results. Most adults fall between 60 and 100 bpm at rest, with fitter individuals trending lower.
When Heart Rate Zones Don’t Apply
If you take beta-blockers or other medications that slow your heart rate, standard target zones won’t work for you. Beta-blockers keep your heart rate from rising the way it normally does during exercise, and you may never reach your calculated target no matter how hard you push. There’s no reliable formula to adjust for this effect because it varies from person to person and medication to medication.
The better alternative is perceived exertion. The Borg Rating of Perceived Exertion Scale asks you to rate how hard you feel you’re working on a scale from 6 (no effort at all) to 20 (maximum effort). Moderate exercise falls around 12 to 14, where you’re breathing harder but can sustain the effort. Vigorous exercise falls around 15 to 17, where holding a conversation becomes difficult. An exercise stress test, supervised by a clinician, can also establish a safe and effective intensity range tailored to your specific heart rate response.
The Talk Test as a Quick Check
You don’t need a heart rate monitor to gauge your intensity. The CDC recommends the talk test as a simple and surprisingly reliable method. If you can talk comfortably but couldn’t sing the words to a song, you’re in the moderate zone. If you can only get out a few words before needing to catch your breath, you’ve crossed into vigorous territory. If you can sing easily, you’re probably not working hard enough to get meaningful cardiovascular benefits.
This works well for people who find constant number-checking distracting or stressful during a workout. It also naturally adjusts as your fitness improves, since the same pace will feel easier over time, prompting you to push a little harder to stay in the right zone.
What Your Heart Rate After Exercise Tells You
How quickly your heart rate drops after you stop exercising is a useful marker of cardiovascular fitness. A healthy recovery is a drop of 18 beats or more within the first minute after stopping. So if you finish a run at 160 bpm and you’re at 142 or lower after 60 seconds of rest, your heart is recovering well.
A slower recovery doesn’t necessarily mean something is wrong, especially if you’re just starting a fitness routine. But it’s a number worth tracking over time. As your cardiovascular fitness improves, your heart rate will drop faster after exercise, your resting heart rate will trend downward, and you’ll need to work harder to reach the same target zones. All three are signs that your heart is getting stronger and more efficient.