Your heart rate during exercise should generally fall between 50% and 85% of your maximum heart rate, depending on how intense you want your workout to be. For moderate exercise like brisk walking, aim for 50% to 70%. For vigorous exercise like running or cycling hard, aim for 70% to 85%. These ranges come from the American Heart Association and apply to most healthy adults.
How to Find Your Maximum Heart Rate
Everything starts with your estimated maximum heart rate. The simplest formula is 220 minus your age. If you’re 40, your estimated max is 180 beats per minute. If you’re 30, it’s 190. This is the ceiling your heart rate shouldn’t exceed during exercise, and it’s the number you’ll use to calculate your target zones.
This formula is a rough estimate. Individual variation is real: two 40-year-olds with different fitness levels and genetics can have noticeably different true maximums. A newer formula (208 minus 0.7 times your age) tends to be slightly more accurate for older adults, but for most people the classic 220-minus-age works well enough as a starting point.
Target Heart Rate by Age
Here’s what the ranges look like in actual numbers. The moderate zone (50% to 70% of max) is appropriate for everyday cardio, and the vigorous zone (70% to 85%) is for harder training sessions.
- Age 25: Max ~195. Moderate: 98–137 bpm. Vigorous: 137–166 bpm.
- Age 30: Max ~190. Moderate: 95–133 bpm. Vigorous: 133–162 bpm.
- Age 35: Max ~185. Moderate: 93–130 bpm. Vigorous: 130–157 bpm.
- Age 40: Max ~180. Moderate: 90–126 bpm. Vigorous: 126–153 bpm.
- Age 45: Max ~175. Moderate: 88–123 bpm. Vigorous: 123–149 bpm.
- Age 50: Max ~170. Moderate: 85–119 bpm. Vigorous: 119–145 bpm.
- Age 55: Max ~165. Moderate: 83–116 bpm. Vigorous: 116–140 bpm.
- Age 60: Max ~160. Moderate: 80–112 bpm. Vigorous: 112–136 bpm.
- Age 65: Max ~155. Moderate: 78–109 bpm. Vigorous: 109–132 bpm.
What Each Zone Actually Does for You
Moderate intensity (50% to 70%) is where most people should spend the bulk of their exercise time. At this level you’re breathing harder than normal but can still hold a conversation. It builds cardiovascular endurance, lowers blood pressure over time, and is sustainable for 30 to 60 minutes or longer.
Vigorous intensity (70% to 85%) pushes your cardiovascular system harder. Talking becomes difficult. You’ll burn more total calories per minute, improve your aerobic capacity faster, and build more stamina. Interval training, tempo runs, and challenging group fitness classes typically land in this range.
Going above 85% of your max puts you into near-maximal effort. This is the territory of sprints and all-out intervals. It’s nearly impossible to sustain for more than about a minute because your body burns through its quick-access energy stores faster than it can replenish them. These short bursts can improve fitness and total calorie burn, but they’re a small piece of a well-rounded routine, not the foundation.
The “Fat Burning Zone” Is Misleading
You’ve probably seen treadmills or fitness trackers label a lower heart rate range as the “fat burning zone,” typically around 60% to 70% of max. The idea is that your body uses a higher percentage of fat for fuel at lower intensities. That part is technically true, but it’s misleading in practice.
At lower intensities, you burn fewer total calories per minute. So while a greater share of those calories comes from fat, the absolute amount of fat burned is less than what you’d burn in a harder workout. A 30-minute vigorous session burns significantly more total calories than 30 minutes at a gentle pace, and your body taps into fat stores once it runs through its quick-energy supply. On top of that, higher-intensity exercise creates an “afterburn effect” where your body continues burning extra calories after the workout ends. If weight loss is your goal, total calories matter more than the fuel mix during the session itself.
How to Track Intensity Without a Monitor
Not everyone wears a heart rate monitor or smartwatch. The simplest alternative is the talk test. During moderate exercise, you can talk but not sing. During vigorous exercise, you can only get out a few words before needing a breath. If you can’t speak at all, you’re likely above 85% and pushing too hard for sustained effort.
A more structured option is the Borg Rating of Perceived Exertion scale, which runs from 6 (no effort at all, like sitting still) to 20 (absolute maximum effort). A rating between 12 and 14 corresponds roughly to moderate intensity. Most workouts should feel “somewhat hard,” meaning they take real effort but you can keep going. This approach is especially useful if medications affect your heart rate, since the scale measures how your body feels rather than relying on a number that may not be accurate for you.
Beta Blockers and Other Medications Change the Rules
Beta blockers, commonly prescribed for high blood pressure and certain heart conditions, slow your heart rate. If you take one, your heart rate during exercise will be lower than the standard formulas predict, and you may never reach your calculated target zone no matter how hard you push. This doesn’t mean the workout isn’t effective. It means heart rate alone isn’t a reliable guide for you.
If you’re on beta blockers or other medications that affect heart rate, the perceived exertion approach described above is a better way to gauge intensity. A stress test performed in a clinical setting can also establish a personalized target heart rate that accounts for the medication’s effects.
Signs You’re Pushing Too Hard
Exercising above your target zone occasionally isn’t dangerous for most healthy people, but certain symptoms during a workout signal that something is wrong. Chest pain or pressure, dizziness, lightheadedness, feeling faint, significant shortness of breath that doesn’t match your effort level, or sudden weakness are all reasons to stop immediately. These can indicate your heart is under more stress than it can handle safely.
Heart Rate Recovery as a Fitness Check
One useful number to track over time is how quickly your heart rate drops after you stop exercising. After a hard effort, pause and check your heart rate, then check again one minute later. A drop of 18 beats per minute or more is considered a good recovery. The faster your heart rate comes down, the fitter your cardiovascular system is. As your fitness improves over weeks and months, you’ll typically see this number get better, which is a more meaningful sign of progress than what your heart rate hits during the workout itself.