Target Heart Rate Calculator
Estimate your maximum heart rate and explore training zones for different exercise intensities. Choose an age-based formula or include your resting heart rate for a more individualised estimate.
Calculate Your Target Heart Rate
Enter your age and select a calculation method. Your results will show estimated beats per minute (bpm) for five training-intensity zones. These estimates are general fitness references, not personalised medical exercise limits.
Choose an age-based formula for a quick estimate. If you know your resting heart rate, the heart rate reserve (Karvonen) method can account for it when estimating training zones.
Your Training Zones
Estimated Heart Rate Training Zones
These are approximate exercise-intensity ranges. You can also use perceived exertion and the talk test to assess intensity. Actual heart-rate responses vary with fitness, medications, health conditions and individual physiology.
Age-based formulas cannot determine a medically safe training heart rate. If you have a cardiovascular condition, take medication that changes your heart rate, or have been advised to limit exercise intensity, seek individual guidance from your healthcare professional. Stop exercising and seek urgent medical help for chest pain, fainting or severe unexpected breathlessness.
What Do Your Target Heart Rate Results Mean?
Your results provide an estimated maximum heart rate, moderate and vigorous exercise ranges, and five training-intensity zones. Each number is a guide to help you understand exercise effort, rather than an exact measurement of your personal cardiovascular capacity.
Estimated Maximum Heart Rate
This is an approximation of the highest heart rate you might reach during maximal physical effort. Age-based formulas use population averages, so your actual maximum can be higher or lower.
Moderate-Intensity Range
Moderate activity raises your breathing and heart rate while generally allowing you to speak in sentences. The calculator displays a commonly used reference range of 50–70% of estimated maximum heart rate, or the corresponding heart rate reserve percentages if selected.
Vigorous-Intensity Range
Vigorous activity typically makes breathing harder and sustained conversation more difficult. The calculator uses a 70–85% reference range, interpreted through the chosen calculation method.
Understanding the Five Training Zones
Very light effort, often associated with gentle movement and easier activity.
Light, sustainable effort commonly associated with comfortable aerobic exercise.
Moderate-to-challenging effort, depending on your fitness and calculation method.
Hard effort that is generally more difficult to maintain for long periods.
Very hard to near-maximal effort, which may not be appropriate for everyone.
These five zones are a convenient training model, not universally standardised physiological thresholds. Different fitness devices, training systems and exercise professionals may use different zone boundaries. The percentages refer to estimated maximum heart rate for the age-based methods and heart rate reserve when the Karvonen method is selected.
The Karvonen method uses heart rate reserve: estimated maximum heart rate minus resting heart rate. It then adds a percentage of that reserve back to your resting rate. Consequently, the same percentage can produce a different bpm result from a simple percentage of maximum heart rate. These two percentage systems should not be treated as interchangeable.
Your estimated zones do not establish a safe upper exercise limit. Heart conditions, medications that alter heart rate, illness and individual fitness can change the meaning of these numbers. If you have a relevant medical condition or have been advised to restrict exercise intensity, obtain individual guidance rather than relying on an age-based estimate.
How Is Target Heart Rate Calculated?
Target heart rate estimates begin with an approximation of maximum heart rate. The calculator then applies training-intensity percentages either directly to that estimated maximum or to your heart rate reserve. Here is how each method works.
Standard Formula: 220 Minus Age
This traditional approach estimates maximum heart rate by subtracting your age from 220. It is simple and widely recognised, but it does not account for differences between individuals.
Tanaka Formula: 208 Minus 0.7 × Age
This alternative age-based equation was developed from research examining the relationship between age and maximum heart rate. It may offer a useful population-level estimate, but it remains subject to individual variation.
Karvonen Method: Heart Rate Reserve
The Karvonen approach incorporates resting heart rate. First, subtract resting heart rate from estimated maximum heart rate to obtain heart rate reserve (HRR). Then apply an intensity percentage to that reserve and add resting heart rate back. Our calculator uses the Tanaka equation to estimate maximum heart rate for this method.
How the Calculator Produces Your Results
Use the selected age-based equation to estimate maximum heart rate in beats per minute.
Calculate training ranges using percentages of estimated maximum heart rate or heart rate reserve.
Round the calculated values to whole beats per minute and display the five training zones.
Comparing the Three Methods
| Method | Inputs | How It Works |
|---|---|---|
| 220 − Age | Age | Uses a traditional age-based estimate of maximum heart rate. |
| Tanaka | Age | Uses an alternative age-based equation for estimated maximum heart rate. |
| Karvonen | Age + resting heart rate | Uses the Tanaka maximum estimate and resting heart rate to calculate heart rate reserve training ranges. |
Maximum heart rate varies substantially between individuals of the same age. Neither the traditional equation nor the Tanaka equation can determine your actual maximum heart rate or establish a medically safe exercise threshold. The Karvonen method incorporates resting heart rate but still relies on an estimated maximum. Use these results as general educational references, especially if you are new to exercise or managing a health condition.
Heart Rate Training Zones Explained
Heart rate zones group exercise into different levels of effort. Lower zones generally feel easier to sustain, while higher zones require more effort and recovery. Our calculator displays five percentage-based zones to help you interpret your estimated training heart rate.
Percentages refer to estimated maximum heart rate for the standard and Tanaka methods, or heart rate reserve when the Karvonen method is selected. These two percentage systems are not interchangeable.
Zone 1 — Very Light Effort
Zone 1 represents the lowest displayed intensity range. It may correspond to easy movement, gentle walking or light activity, although the actual effort you experience depends on fitness and the calculation method used.
Talk test: You can generally speak comfortably and breathe without substantial difficulty.
Zone 2 — Light Aerobic Effort
Zone 2 is commonly associated with comfortable, steady exercise. Examples may include brisk walking, relaxed cycling or easy jogging for someone whose fitness makes those activities manageable.
Talk test: Conversation is usually possible, although breathing may be faster than at rest.
Zone 3 — Moderate-to-Challenging Effort
Zone 3 represents a higher percentage of the selected heart rate measure. It may feel moderately challenging or harder, depending on individual fitness, resting heart rate and the zone model being used.
Talk test: Speaking may still be possible, but maintaining a long conversation can become more difficult.
Zone 4 — Hard Effort
Zone 4 is associated with demanding activity and increased breathing effort. Some structured training programmes use higher-intensity intervals, but such exercise is not necessary or appropriate for everyone.
Talk test: Speaking in full sentences may be difficult, with breathing noticeably heavier.
Zone 5 — Very Hard to Near-Maximal Effort
Zone 5 approaches the estimated maximum heart rate and may represent very strenuous exercise. It is typically difficult to sustain and may carry additional risks for people who are unaccustomed to intense activity or have certain health conditions.
Talk test: Speaking more than a few words may be difficult because of the effort required.
Three Things to Remember About Training Zones
Age-based maximum heart rate formulas cannot predict your exact physiological thresholds. Actual exercise intensity can differ from the displayed zone.
Breathing, perceived exertion and your ability to speak provide useful additional clues about how hard you are exercising.
Exercise benefits do not require consistently training near maximum heart rate. Appropriate intensity depends on your goals, fitness and health.
Different sports watches, coaching systems and exercise guidelines may define zones differently. Some use percentages of maximum heart rate, others use heart rate reserve, lactate thresholds or ventilatory thresholds. Our five-zone display is an educational reference, not a physiological assessment or a personalised exercise prescription. If you have a heart condition, take heart-rate-affecting medication or have exercise restrictions, follow individual clinical advice.
Maximum Heart Rate vs Resting Heart Rate: What’s the Difference?
Maximum heart rate and resting heart rate describe two different aspects of cardiovascular function. Understanding both helps explain why two people of the same age may receive different target heart rate estimates when using the heart rate reserve method.
Your Heart Rate at Maximum Effort
Maximum heart rate (HRmax) is the highest heart rate an individual can achieve during maximal exertion. It is commonly expressed in beats per minute (bpm).
Age-based equations provide approximate estimates, but your actual maximum heart rate can differ considerably from the calculated figure. A higher maximum heart rate does not automatically indicate better fitness.
Your Heart Rate While at Rest
Resting heart rate (RHR) is the number of heartbeats per minute while you are awake, calm and physically at rest.
For many adults, a resting heart rate of approximately 60–100 bpm is commonly referenced, although trained athletes may have lower values. Fitness, medication, illness, stress and other factors can affect it.
What Is Heart Rate Reserve?
The Difference Between Maximum and Resting Heart Rate
Heart rate reserve (HRR) is calculated by subtracting resting heart rate from maximum heart rate. The Karvonen method uses this reserve to estimate exercise training ranges.
Estimated maximum heart rate: 184 bpm
Resting heart rate: 65 bpm
Heart rate reserve: 184 − 65 = 119 bpm
At 70% HRR: 65 + (119 × 0.70) ≈ 148 bpm
What Can Influence Your Heart Rate?
Maximum heart rate tends to decline with age on average, but substantial differences exist between individuals.
Resting heart rate may change with aerobic conditioning, recovery, sleep and overall health.
Some medicines and cardiovascular or other medical conditions can change resting and exercise heart rate responses.
A lower resting heart rate is not always a sign of better health, and a higher maximum heart rate is not necessarily a fitness advantage. Unexplained changes in resting heart rate, symptoms such as dizziness or fainting, or concerns about exercise heart rate should be discussed with a healthcare professional. The calculator provides estimates and cannot diagnose a heart condition or determine a safe exercise limit.
Using Heart Rate Zones for Different Fitness Goals
Your target heart rate can help you understand exercise intensity, but the most suitable approach depends on your experience, health, preferences and goals. The examples below show how different levels of effort may be used in a balanced fitness routine.
Starting an Exercise Routine
If you are beginning regular exercise, manageable activities such as walking, gentle cycling or swimming may help you develop consistency.
Rather than chasing a particular bpm number, focus on an effort you can sustain comfortably and increase activity gradually as appropriate.
Building Aerobic Endurance
Steady walking, cycling, jogging or similar activities can contribute to aerobic endurance when performed at an appropriate intensity and duration.
Lower-to-moderate effort may be useful for longer sessions, although the relevant heart rate zone differs between people and training systems.
Improving General Cardiovascular Fitness
Regular moderate-intensity activity can support cardiovascular fitness. Some people also include vigorous activity when appropriate for their health and fitness.
Consistency, adequate recovery and overall activity matter more than reaching a particular heart rate zone during every workout.
Structured Higher-Intensity Training
Some experienced exercisers use more demanding intervals as part of a structured training programme.
Higher-intensity work is not required for everyone, and estimated heart rate zones should not be used as proof that strenuous exercise is safe for an individual.
How to Use Your Calculator Results in Practice
Select exercise that matches your ability, preferences and any medical advice you have received.
Compare your measured heart rate with the estimated range, while also considering breathing and perceived exertion.
Increase duration or intensity gradually when appropriate, allowing time for recovery and adaptation.
Not necessarily. Health and fitness benefits can come from a variety of appropriately chosen activities and intensities. A heart rate zone is one monitoring tool, not a requirement for a successful workout.
If you have cardiovascular disease, symptoms during activity, significant exercise limitations or take medicines that affect heart rate, obtain personalised exercise guidance. Stop activity if you develop chest pain, faintness or severe unexpected breathlessness, and seek urgent medical help when appropriate. This calculator does not prescribe an exercise programme or determine medical fitness for exercise.
How to Measure Your Heart Rate
You can measure your heart rate manually or with a monitoring device. Accurate readings are useful when comparing your exercise effort with the estimated target heart rate ranges from the calculator.
Method 1: Check Your Pulse Manually
You can find your pulse at your wrist and count the beats to estimate your heart rate.
- Place your index and middle fingers gently on the thumb side of your opposite wrist.
- Adjust your fingers until you feel a steady pulse.
- Count the beats for 30 seconds.
- Multiply the count by two to estimate beats per minute.
For a more reliable resting measurement, counting for a full 60 seconds may be preferable, especially if your pulse feels irregular. Avoid using your thumb because it has its own pulse.
Method 2: Use a Heart Rate Monitor
Fitness watches, wrist-based trackers and chest-strap monitors can display heart rate during exercise.
- Fitness watches: Convenient for tracking trends and everyday activity.
- Chest straps: Often provide more reliable heart rate measurements during movement when properly fitted.
- Exercise equipment: Some machines provide heart rate estimates through hand sensors, but readings can vary.
Motion, poor contact, device fit and changes in exercise intensity can affect readings. If a number seems inconsistent with how you feel, check the fit or verify your pulse manually.
How to Measure Resting Heart Rate
Measure when awake, calm and relaxed. Before getting out of bed in the morning is a commonly used option.
Rest quietly, then measure your pulse for 60 seconds or use a properly fitted monitor.
Track measurements across several days to understand your usual resting range rather than relying on one result.
Comparing Heart Rate Measurement Methods
| Method | Best Use | Main Limitation |
|---|---|---|
| Manual pulse check | Occasional resting or post-exercise checks | Counting errors and delays after stopping exercise can affect results. |
| Wrist-based fitness tracker | Convenient activity and trend monitoring | Movement, fit and sensor limitations may affect accuracy. |
| Chest-strap monitor | Continuous heart rate tracking during workouts | Requires correct positioning and a compatible recording device. |
| Exercise-machine sensors | Quick approximate checks while using equipment | Hand position and sensor quality can produce inconsistent readings. |
Heart rate is only one way to assess exercise intensity. Your breathing, ability to speak and perceived effort can provide additional information, particularly when a device reading appears unreliable or medications alter your heart rate response.
Seek medical assessment for unexplained persistent changes in resting heart rate, a noticeably irregular pulse or concerning symptoms. If you experience chest pain, fainting or severe unexpected breathlessness, stop exercising and seek urgent medical help. Do not use this calculator or consumer fitness devices to diagnose an abnormal heart rhythm or determine whether strenuous exercise is safe.
Factors That Affect Your Heart Rate
Your heart rate is influenced by more than exercise intensity. Age, fitness, temperature, hydration, sleep, medication and other factors can affect your readings. Understanding these influences helps you interpret your target heart rate results more realistically.
Age and Individual Biology
Maximum heart rate tends to decrease with age on average, but individuals of the same age can have different maximum heart rates. Age-based formulas provide estimates rather than exact personal values.
Fitness and Training
Regular aerobic exercise may lower resting heart rate over time and change how your heart rate responds to familiar activities. Maximum heart rate is not a direct measure of fitness.
Heat and Humidity
Hot or humid conditions can increase cardiovascular strain. Your heart rate may be higher than usual during a workout, even when your pace or workload remains similar.
Hydration and Fluid Loss
Dehydration can contribute to an elevated heart rate during activity. Fluid needs vary according to conditions, exercise duration and individual circumstances.
Sleep, Stress and Recovery
Poor sleep, emotional stress and incomplete recovery can affect resting and exercise heart rate. A higher-than-usual reading may reflect temporary strain rather than a change in fitness.
Medication and Health Conditions
Some medications, including beta blockers, can reduce the heart rate response to exercise. Illness, fever and certain medical conditions can also change heart rate patterns.
Caffeine and Stimulants
Caffeine, nicotine and some stimulant-containing products or medicines may increase heart rate in certain people. The effect depends on the individual, dose and timing.
Exercise Type and Position
Walking, cycling, running and resistance training can produce different heart rate responses. Body position, muscle involvement and movement patterns can influence readings.
Measurement Accuracy
Wrist-monitor fit, movement, sensor contact and timing can affect recorded values. A single unexpected reading does not necessarily represent your true heart rate.
Why Your Heart Rate May Differ Between Workouts
Comfortable Walk on a Cool Day
You complete a familiar walk in mild conditions after adequate rest. Your measured heart rate may remain relatively steady at a comfortable effort.
The Same Walk on a Hot Day
You repeat the walk at a similar pace in hotter conditions. Your heart rate may rise because your body is working harder to regulate temperature and maintain circulation.
How to Interpret Changing Readings
Compare readings across similar activities and conditions instead of relying on a single workout.
Use perceived exertion, breathing and the talk test alongside your heart rate reading.
Consider reducing intensity when heat, illness, fatigue or other factors make exercise feel unusually difficult.
Seek medical advice for persistent unexplained changes in resting heart rate, an irregular pulse or unusual exercise responses. Stop exercising and seek urgent medical help for chest pain, fainting or severe unexpected breathlessness. If you take heart-rate-affecting medication or have a cardiovascular condition, use personalised clinical guidance rather than relying solely on estimated training zones.
Common Target Heart Rate Mistakes to Avoid
Target heart rate calculations are useful for understanding exercise intensity, but incorrect assumptions can make the results misleading. These common mistakes explain what to watch for when using heart rate formulas, fitness trackers and training zones.
Treating Estimated Maximum Heart Rate as an Exact Number
The standard 220 minus age formula and the Tanaka formula estimate maximum heart rate using population-level relationships. Neither can predict an individual’s exact maximum.
Use the calculated maximum as a general reference, not a confirmed physiological measurement or medically safe upper limit.
Confusing Maximum Heart Rate With a Training Target
Your estimated maximum heart rate is not a number you should aim to reach during every workout. Exercise at or near maximum effort is demanding and may be inappropriate for many people.
Choose an intensity appropriate for your fitness, goals and health rather than trying to reach your estimated maximum.
Mixing Maximum Heart Rate and Heart Rate Reserve Percentages
Seventy percent of maximum heart rate is not the same calculation as seventy percent of heart rate reserve. The Karvonen method adds a portion of the reserve back to resting heart rate.
Check which method is selected before comparing zone percentages or bpm results from different calculators and devices.
Assuming All Five-Zone Systems Are Identical
Different training platforms use different zone boundaries, formulas and labels. A zone called “Zone 2” on one device may not match the same label elsewhere.
Compare the actual percentage method and boundaries, not just the zone number or name.
Using an Inaccurate Resting Heart Rate
Measuring immediately after walking, caffeine or emotional stress may produce a reading that does not reflect your usual resting heart rate. This affects Karvonen results.
Measure while calm and rested, preferably under consistent conditions, and consider several readings over time.
Trusting Every Smartwatch Reading
Optical wrist sensors can be affected by movement, fit and sensor contact. An unexpected reading may be a measurement error rather than a true change in heart rate.
Check device fit and compare questionable readings with a manual pulse measurement or another suitable monitor.
Ignoring Medication, Symptoms or Medical Conditions
Beta blockers and some other medicines can change the heart rate response to exercise. Certain health conditions can also make standard training-zone estimates unsuitable.
Seek individual clinical guidance when medication, symptoms or health conditions may affect safe exercise intensity.
Believing Higher Heart Rate Always Means a Better Workout
Exercise benefits are not determined solely by how high your heart rate rises. Duration, consistency, recovery, overall activity and appropriate effort also matter.
Use heart rate as one indicator of effort, alongside the talk test, perceived exertion and a balanced exercise routine.
Example: Why the Calculation Method Matters
Estimated maximum = 220 − 35 = 185 bpm. At 70% of estimated maximum, the result is approximately 130 bpm.
Using the Tanaka estimate of 183.5 bpm and a resting heart rate of 65 bpm, 70% of heart rate reserve produces approximately 148 bpm.
The difference comes from the formulas and inputs, not necessarily a calculation error. Our calculator identifies the selected method so you can interpret the displayed ranges correctly.
If exercise causes chest pain, faintness, severe unexpected breathlessness or other concerning symptoms, stop rather than trying to maintain a calculated zone. Seek urgent medical help for serious symptoms. Heart rate estimates are educational tools and cannot establish an individual’s medically safe exercise intensity.
Target Heart Rate Calculator FAQs
Find answers to common questions about calculating target heart rate, interpreting training zones and using heart rate readings during exercise.
01What is a target heart rate?
A target heart rate is an estimated range of heartbeats per minute associated with a chosen exercise intensity. It can help you monitor effort during physical activity, but it is not a medically established safe range for every individual.
02How do I calculate my target heart rate?
One common approach estimates maximum heart rate using 220 minus age, then multiplies that estimate by an exercise intensity percentage. For example, at age 40, the estimated maximum is 180 bpm, and 70% of that value is 126 bpm.
Other approaches include the Tanaka formula and the Karvonen heart rate reserve method. The results can differ because the formulas use different assumptions and inputs.
03What is a normal target heart rate during exercise?
There is no single normal exercise heart rate for everyone. Target ranges depend on age, the calculation method, fitness, medication and the intended activity intensity. Some general guidance uses approximately 50–70% of estimated maximum heart rate for moderate intensity and 70–85% for vigorous intensity, but these are broad estimates rather than personalised limits.
04Is the 220 minus age formula accurate?
The 220 minus age formula is a convenient estimate, but individual maximum heart rates can differ substantially from its prediction. The Tanaka formula, 208 − (0.7 × age), is another population-based estimate. Neither formula can determine an individual’s exact maximum heart rate.
05What is the difference between maximum heart rate and resting heart rate?
Maximum heart rate refers to the highest rate your heart can reach during maximal exertion. Resting heart rate is your heart rate when you are awake, calm and at rest. The difference between them is called heart rate reserve, which is used in the Karvonen method.
06What is the Karvonen formula?
The Karvonen formula estimates a target heart rate using heart rate reserve: Target HR = Resting HR + [(Maximum HR − Resting HR) × Intensity].
Our calculator uses the Tanaka maximum heart rate estimate when you select Karvonen. This method requires a resting heart rate measurement, and its percentages should not be treated as interchangeable with percentages of maximum heart rate.
07What are the five heart rate training zones?
Five-zone systems divide exercise intensity into progressively higher ranges. This calculator displays Zone 1: 50–60%, Zone 2: 60–70%, Zone 3: 70–80%, Zone 4: 80–90% and Zone 5: 90–100% using the selected calculation method.
Other devices and training programmes may use different boundaries, so zone numbers are not universally standardised.
08Is Zone 2 the best heart rate zone for fat loss?
No single numbered zone guarantees better fat loss. Lower-intensity exercise may use a higher proportion of fat as fuel, but long-term weight management depends on multiple factors, including overall energy balance, activity, nutrition and consistency.
Also, the term Zone 2 can refer to different intensity ranges depending on the training system.
09Can medication affect my target heart rate?
Yes. Medicines such as beta blockers can reduce your heart rate response to exercise, while other medications may affect it differently. Standard age-based zones may not be suitable in these circumstances. Ask your treating clinician about appropriate exercise intensity guidance rather than adjusting medication or exercise targets yourself.
10Should I stop exercising if my heart rate exceeds the calculated target?
Not necessarily. A calculated target range is an estimate, not a fixed safety threshold. However, you should reduce or stop activity if the effort feels inappropriate or you develop concerning symptoms.
Stop exercising and seek urgent medical help for chest pain, fainting or severe unexpected breathlessness. People with relevant health conditions or medications should follow individual medical guidance.
Sources & References
Our Target Heart Rate Calculator uses established estimation formulas and general exercise-intensity guidance. The references below explain the scientific background, calculation methods and limitations discussed throughout this page.
Tanaka, Monahan & Seals (2001) — Age-Predicted Maximal Heart Rate Revisited
Published in the Journal of the American College of Cardiology. This research supports the age-predicted maximum heart rate equation of 208 − (0.7 × age) used by the calculator’s Tanaka and Karvonen options.
View research on PubMed ↗American Heart Association — Target Heart Rates Chart
Explains estimated maximum heart rate, target heart rate zones and commonly used exercise-intensity percentages. Supports the general interpretation of age-based target heart rate ranges.
Read AHA guidance ↗CDC — Measuring Physical Activity Intensity
Describes ways to assess exercise intensity, including the talk test, perceived exertion and target heart rate. Supports using breathing and perceived effort alongside heart rate readings.
Read CDC guidance ↗World Health Organization — Guidelines on Physical Activity and Sedentary Behaviour
Provides recommendations for regular physical activity, including weekly moderate- and vigorous-intensity aerobic exercise and muscle-strengthening activity. Supports the page’s broader guidance on exercise consistency and gradual progression.
Read WHO recommendations ↗How These References Are Applied
Maximum heart rate: The calculator offers the conventional 220 − age estimate and the Tanaka equation. Both are population-based approximations, not individually measured maximum heart rates.
Heart rate reserve: The Karvonen option uses resting heart rate and the Tanaka estimate of maximum heart rate to calculate target values from heart rate reserve.
Training intensity: The moderate and vigorous percentage ranges are general educational guides. The five-zone display uses a consistent percentage framework selected for this calculator; its zone boundaries are not a universal physiological classification.
Clinical limitations: The sources provide general research and public-health context. They do not validate a particular calculated bpm range as medically safe for an individual.
This calculator and its references are intended for general education, not diagnosis, treatment or personalised exercise prescription. Individual needs may differ because of health conditions, medications, fitness and other factors. Consult an appropriately qualified healthcare professional when personalised guidance is needed. Read our Medical Disclaimer.
Find Your Estimated Target Heart Rate
Explore your estimated exercise heart rate ranges, compare calculation methods and better understand how training intensity relates to your fitness goals. Our free calculator makes it easy to get started.
Results are estimates for general educational use and do not establish a medically safe exercise intensity. Follow individual medical advice when relevant.