Your heart rate during exercise should fall between 50% and 85% of your maximum heart rate, depending on how hard you’re working. For moderate exercise like brisk walking, aim for 50% to 70%. For vigorous exercise like running or cycling hard, aim for 70% to 85%. Your maximum heart rate is roughly 220 minus your age, which means the actual numbers shift significantly depending on how old you are.
Target Heart Rate by Age
The American Heart Association publishes a straightforward chart based on the formula 220 minus your age. Here’s what it looks like across age groups:
- Age 20: Max heart rate of 200 bpm, target zone 100 to 170 bpm
- Age 30: Max heart rate of 190 bpm, target zone 95 to 162 bpm
- Age 40: Max heart rate of 180 bpm, target zone 90 to 153 bpm
- Age 50: Max heart rate of 170 bpm, target zone 85 to 145 bpm
- Age 60: Max heart rate of 160 bpm, target zone 80 to 136 bpm
- Age 70: Max heart rate of 150 bpm, target zone 75 to 128 bpm
That target zone (50% to 85%) is broad on purpose. The lower end covers a comfortable walk, while the upper end covers an all-out effort you can only sustain for minutes. Where you should land within that range depends on your goals and fitness level.
How to Calculate Your Max Heart Rate
The classic formula, 220 minus your age, has been used since the 1970s. It’s simple and reasonably accurate for most adults, but it tends to underestimate the true max heart rate in older adults. A newer formula, 208 minus 0.7 times your age, corrects for that and is generally considered more reliable for people over 40.
For a 50-year-old, the difference matters: the classic formula gives a max of 170 bpm, while the newer one gives 173. For a 30-year-old, both formulas land close to 190. Either way, these are estimates. Individual max heart rates can vary by 10 to 15 beats in either direction, so treat these numbers as starting points rather than hard limits.
A More Personalized Approach
The standard percentage-of-max method ignores one important variable: your resting heart rate. Someone with a resting heart rate of 55 bpm has a much larger working range than someone resting at 80 bpm, even if they’re the same age. The Karvonen method accounts for this by using your heart rate reserve, which is simply your max heart rate minus your resting heart rate.
To find a personalized target, multiply your heart rate reserve by your desired intensity percentage, then add your resting heart rate back. For example, a 40-year-old with a resting heart rate of 65 bpm has a heart rate reserve of 115 (180 minus 65). At 60% intensity, that’s 69 plus 65, giving a target of 134 bpm. This method is commonly used in cardiac rehabilitation programs, where patients typically aim for 60% to 80% of heart rate reserve.
What Each Heart Rate Zone Feels Like
Heart rate zones break the range from rest to max effort into five tiers. Each one has a distinct feel and a different training benefit.
Zone 1 (50% to 60% of max) is a warmup or recovery pace. You can hold a full conversation without any effort. Think of a casual walk or gentle stretching.
Zone 2 (60% to 70%) is the endurance-building sweet spot. You can still talk, but you might pause mid-sentence to catch your breath. Brisk walking, easy jogging, and long bike rides typically fall here. Most general fitness benefits come from spending time in this zone.
Zone 3 (70% to 80%) feels comfortably hard. Conversation drops to short phrases. This is where you build both strength and cardiovascular endurance, typical of a steady-state run or a moderately challenging group fitness class.
Zone 4 (80% to 90%) is where talking takes real effort. You’re pushing toward your limit, building speed and power. Interval training and tempo runs often push into this zone for short bursts.
Zone 5 (90% to 100%) is a full sprint effort. You’re gasping, not talking. This trains your heart at peak capacity and builds fast-twitch muscle fibers, but you can only sustain it for 30 seconds to a few minutes. Most people rarely need to train here.
When Heart Rate Isn’t Reliable
Certain medications fundamentally change how your heart responds to exercise. Beta blockers, commonly prescribed for high blood pressure and heart conditions, lower both resting and peak heart rate significantly. Research shows that people on beta blockers have a resting heart rate about 14 bpm lower than normal and a max heart rate roughly 19% lower. A 50-year-old on beta blockers might max out around 116 bpm instead of 145 bpm, making the standard heart rate zones meaningless.
If you take medications that affect heart rate, the Borg Rating of Perceived Exertion scale offers a useful alternative. It’s a simple self-assessment: you rate how hard you feel you’re working on a scale from 6 (no effort at all) to 20 (absolute maximum). A rating of 12 to 14, described as “somewhat hard,” corresponds roughly to moderate-intensity exercise. You don’t need any device, just honest self-awareness. If you can speak in short sentences but not sing, you’re likely in the moderate range.
What Your Recovery Heart Rate Reveals
How quickly your heart rate drops after you stop exercising is one of the best indicators of cardiovascular fitness. A healthy heart rate recovery is a drop of at least 18 beats within the first minute of rest. The faster and larger that drop, the more efficiently your heart and nervous system are working together.
A sluggish recovery, where your heart rate stays elevated well after you stop moving, can signal that your cardiovascular system is under strain. People with poor heart rate recovery are at higher risk for coronary artery disease, heart failure, high blood pressure, and diabetes. This holds true even in people who haven’t been diagnosed with any heart condition. If you wear a fitness tracker, your post-exercise heart rate trend over weeks and months is one of the most meaningful numbers to watch. As your fitness improves, you should see that one-minute recovery number climb.
Warning Signs You’ve Pushed Too Hard
Exercising near your max heart rate is physically uncomfortable but generally safe for healthy adults doing short bursts. What matters is recognizing symptoms that go beyond normal exertion. Chest pain, dizziness, lightheadedness, fainting, or sudden shortness of breath that feels disproportionate to the effort are all signals to stop immediately. A racing or pounding heartbeat that feels irregular, with skipped beats or a fluttering sensation, also warrants attention.
These symptoms don’t always mean something serious, but they can indicate an abnormal heart rhythm. The distinction between “I’m working hard” and “something feels wrong” is usually intuitive. If you feel a sense of alarm rather than just fatigue, trust that instinct and stop.