Part of:Fitness & Exercise Guide: Complete Workout, Calories & Training Reference 2026
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Heart Rate Calculator

Calculate target heart rate zones for optimal cardio training using Karvonen formula. Find fat-burning, aerobic, and anaerobic zones based on age and resting...

Heart Rate Zone Calculator

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Maximum Heart Rate (MHR) is estimated by the 220 − age formula (e.g., age 40 → MHR = 180 bpm), with a standard deviation of ±10–12 bpm. The American Heart Association recommends exercising at 50–85% of MHR. The Karvonen formula gives a more precise Target Heart Rate: THR = (MHR − Resting HR) × intensity% + Resting HR. Normal resting HR: 60–100 bpm; trained athletes: 40–60 bpm. Five training zones: Zone 1 (50–60%), Zone 2 (60–70% fat-burn), Zone 3 (70–80% aerobic), Zone 4 (80–90% lactate threshold), Zone 5 (90–100% VO₂ max).

Heart Rate Zone Training Guide

Everything you need to know about heart rate zones, the Karvonen formula, and training science

220−age
Max HR Formula
5 zones
Training Zones
60–80%
Fat Burn Zone
1968
Karvonen Refined

What is Heart Rate Zone Training?

Heart rate zone training is a method of exercising at specific intensities — measured by heart rate — to achieve targeted physiological adaptations. By keeping your heart rate within defined zones, you can optimize whether you are burning fat, building aerobic capacity, improving lactate threshold, or developing peak power.

Your heart rate during exercise is one of the best real-time indicators of exercise intensity. Unlike pace or power, heart rate reflects how hard your cardiovascular system is actually working — accounting for factors like fitness, fatigue, heat, and hydration.

The Karvonen formula (Heart Rate Reserve method) is the gold standard for calculating personalized zones because it accounts for your individual resting heart rate — a key indicator of cardiovascular fitness. A trained athlete with a resting HR of 40 bpm will have very different zones than a sedentary person with 80 bpm, even if they share the same maximum heart rate.

Maximum Heart Rate: The Foundation

220 − Age Formula

The most widely used formula, popularized in the 1970s. Simple to calculate but has a standard deviation of ±10–12 bpm. Works as a reasonable estimate for most people.

Max HR = 220 − age

Tanaka Formula (2001)

Developed by Hirofumi Tanaka et al. at the University of Colorado. More accurate for older adults — produces lower max HR estimates above age 40.

Max HR = 208 − (0.7 × age)

The Karvonen Formula (Heart Rate Reserve)

Developed by Finnish physiologist Martti Karvonen in 1957 and refined in 1968, this formula calculates target heart rate based on heart rate reserve — the difference between maximum and resting heart rate. It is far more accurate than simple percentage-of-max calculations because it accounts for individual fitness level.

// Karvonen Formula
Target HR = (HRmax - HRrest) × intensity + HRrest
// Example: Age 40, Resting HR 65, Zone 2 (60-70% HRR)
Max HR = 220 − 40 = 180 bpm
HR Reserve = 180 − 65 = 115 bpm
Zone 2 Low = (115 × 0.60) + 65 = 134 bpm
Zone 2 High = (115 × 0.70) + 65 = 146 bpm

Why Karvonen Is Superior to Simple % of Max HR

A trained athlete with resting HR 45 bpm and a sedentary person with resting HR 75 bpm will have different training zones even with the same max HR. Simple % of max HR treats them identically — the Karvonen formula recognizes their different fitness levels and prescribes appropriately different intensities.

The 5 Heart Rate Training Zones

Training zones represent distinct physiological states. Each zone produces different adaptations and suits different training goals. BPM ranges below are for a 40-year-old with resting HR 65 bpm (Max HR 180, HRR 115).

Zone% HRRBPM (40yo)BenefitsDuration
Z1 Recovery50–60%123–134Active recovery, blood flow, warm-upUnlimited
Z2 Endurance60–70%134–146Fat burning, aerobic base, mitochondrial growth30–180 min
Z3 Tempo70–80%146–157Aerobic capacity, muscular endurance20–60 min
Z4 Threshold80–90%157–169Lactate threshold, race performance gains10–30 min
Z5 VO₂ Max90–100%169–180Max aerobic capacity, speed development1–8 min intervals

Max Heart Rate Decline with Age

Maximum heart rate naturally declines approximately 1 bpm per year from age 20. This is why HR zones must be recalculated as you age — a 60-year-old cannot be expected to reach the same HR as a 25-year-old.

Age220-age Max HRTanaka Max HRZ2 Range (60–70%)
20200194120–140
30190187114–133
40180180108–126
50170173102–119
6016016696–112
7015015990–105

Max HR Formula Comparison

FormulaEquationAge 30Age 50Age 70Notes
220−age220 − age190170150Overestimates older adults
Tanaka208 − 0.7×age187173159Better for 40+ adults
Fox200 − 0.5×age185175165Less decline with age
Gellish206.9 − 0.67×age187173160Longitudinal study derived

History of Heart Rate Training Science

1957
Åstrand & Ryhming Studies
Per-Olof Åstrand and Irma Ryhming published landmark research on cardiovascular response to exercise, establishing the foundation for heart rate-based intensity prescription and exercise physiology.
1968
Karvonen Formula Refined
Martti Karvonen's 1957 Heart Rate Reserve method was refined and validated, becoming the standard for individualized training zone calculation used by exercise physiologists worldwide.
1977
220−age Popularized
Dr. William Haskell inadvertently popularized the 220−age formula. He himself later called it 'not my formula' — it was never actually published in a peer-reviewed paper but spread through textbooks.
1982
First Polar HR Monitor
Polar Electro introduced the world's first wireless heart rate monitor for athletes, making real-time zone monitoring accessible outside laboratory settings for the first time.
1994
Polarized Training Model
Stephen Seiler's research identified the '80/20' polarized training approach — 80% low intensity (Z1–Z2), 20% high intensity (Z4–Z5), with minimal Z3 — used by elite endurance athletes globally.
2001
Tanaka Formula Published
Hirofumi Tanaka published a meta-analysis in the Journal of the American College of Cardiology proposing the Tanaka formula (208 − 0.7×age) as a more accurate alternative for older adults.
2010+
Wearables Revolution
Fitbit, Apple Watch, Garmin and other consumer wearables made continuous HR monitoring mainstream, enabling millions to train by heart rate zones outside laboratory or gym settings.

Key Research

American Heart Association

Exercise Intensity Guidelines

The AHA recommends 150 min/week moderate intensity (64–76% max HR) or 75 min/week vigorous (77–93% max HR) for cardiovascular health. Both Zone 2 and Zone 4 training satisfy these recommendations.

ACSM Exercise Guidelines

Aerobic Exercise Intensity

The American College of Sports Medicine defines moderate exercise as 40–59% HRR and vigorous as 60–89% HRR. Their position stand explicitly recommends the Karvonen method for individualized zone prescription.

J. American College of Cardiology (2001)

Tanaka Formula Validation

Tanaka et al. analyzed 351 studies (18,712 subjects) to derive and validate a new max HR prediction formula, showing significantly improved accuracy for adults over 40 years old compared to 220−age.

Heart Rate Training: Myths vs. Facts

Myth

You must always train in the 'fat burning zone' to lose weight

Fact

Total caloric expenditure matters more than fuel source. Zone 2 burns a higher percentage of fat, but higher intensity zones burn more total calories per minute. Total caloric deficit drives fat loss, not the fuel mix during exercise.

Myth

220 − age gives an accurate max heart rate

Fact

It is a population average with ±10–12 bpm standard deviation. Up to one in three people will be significantly wrong. The Tanaka formula (208 − 0.7×age) is more accurate for adults over 40, and a lab test is the gold standard.

Myth

Higher heart rate always means a better workout

Fact

Chronic high-intensity training leads to overtraining syndrome. Elite endurance athletes spend 80% of training in Zone 1–2. Consistent Zone 2 training builds the aerobic engine systematically and is more sustainable.

Myth

Wrist HR monitors are accurate enough for serious zone training

Fact

Optical wrist sensors are accurate at rest (±2–5 bpm) but can be off by 15–25+ bpm during high-intensity or grip-heavy activities. Chest straps using ECG technology remain the gold standard for accurate zone training.

Myth

A high resting heart rate does not matter for health

Fact

Resting HR above 80 bpm is associated with increased cardiovascular risk. Research shows each 10 bpm increase in resting HR correlates with approximately 18% higher all-cause mortality risk. Regular aerobic training lowers resting HR.

Myth

Zone 3 training is the most effective for fitness gains

Fact

Zone 3 may be the least effective for most goals — too hard to build aerobic base and too easy for VO₂max development. Exercise scientists call it 'no man's land.' Polarized training (mostly Z2 + some Z4/Z5) produces superior adaptations.

Frequently Asked Questions

How accurate is the 220 − age max heart rate formula?+
The 220 − age formula is a population average with a standard deviation of approximately ±10–12 bpm. This means about two-thirds of people fall within 10–12 bpm of the prediction — but the remaining third could be off by much more. For a 40-year-old, the true max HR range could reasonably span 158–202 bpm. Genetics, training status, sex, and medications all affect true max HR. The only way to know your actual max HR is a laboratory stress test or an all-out field test under supervision. For zone training, a ±10 bpm error translates to roughly ±6–7 bpm in your zone boundaries — meaningful but not disqualifying for recreational athletes starting out.
What is the best heart rate zone for burning fat?+
Zone 2 (60–70% HRR, conversational pace) oxidizes the highest proportion of fat — approximately 60–70% of energy comes from fat at this intensity. However, Zone 4 burns more total calories per minute, even though a lower percentage comes from fat. For endurance athletes and those with ample training time, Zone 2 is ideal for fat adaptation, mitochondrial development, and long-term metabolic health. For time-constrained individuals, higher-intensity intervals and Zone 4 threshold work are more time-efficient. The best zone for fat loss is ultimately the one you can sustain consistently over weeks and months, creating the total caloric deficit needed for results.
What should my resting heart rate be?+
For adults, a normal resting heart rate is 60–100 bpm. Fit individuals typically sit at 50–70 bpm, and elite endurance athletes can be as low as 30–40 bpm (Miguel Indurain famously had a resting HR of 28 bpm during his Tour de France peak years). A resting HR below 60 bpm generally indicates good cardiovascular fitness. Above 80 bpm is associated with increased health risk. Measure resting HR first thing in the morning before getting out of bed, averaged over 3–5 consecutive days for accuracy. With consistent aerobic training, expect your resting HR to drop 10–15 bpm over 12 weeks — one of the most reliable signs your fitness is improving.
What is Zone 2 training and why is it so popular?+
Zone 2 training (60–70% HRR, conversational pace) has gained enormous popularity following research by Peter Attia, Inigo San Millan, and Stephen Seiler. It primarily stimulates mitochondrial biogenesis — growing more and larger mitochondria in slow-twitch muscle fibers. Mitochondria are the cellular engines that burn fat and produce ATP aerobically. More mitochondria means greater aerobic capacity, better fat oxidation, improved metabolic health, and measurably slower biological aging. Zone 2 also improves insulin sensitivity and reduces systemic inflammation. Most recreational athletes dramatically under-invest in Zone 2, defaulting to the "moderate zone" (Z3) that is too hard to build aerobic base but too easy to provide quality high-intensity stimulus.
Why does my heart rate spike excessively during exercise?+
Several factors cause disproportionately high heart rate during exercise: (1) Dehydration — even 2% body weight loss raises HR by 5–8 bpm at the same intensity as blood volume decreases. (2) Heat — exercising in hot weather increases HR by 10–20 bpm as blood redirects to skin for cooling. (3) Caffeine — can raise exercise HR by 5–10 bpm by stimulating the sympathetic nervous system. (4) Overtraining — elevated submaximal HR is a classic early sign of accumulated fatigue and underrecovery. (5) Low aerobic fitness — if your aerobic base is underdeveloped, your heart must work harder at lower intensities; consistent Zone 2 training will lower this over time. (6) Subclinical illness — even mild illness before symptoms appear reliably raises both resting and exercise HR by 3–10 bpm.
What are the key signs of overtraining based on heart rate?+
Heart rate is one of the most sensitive overtraining biomarkers. Key warning signs: (1) Elevated resting HR — more than 5–7 bpm above your normal baseline indicates accumulated fatigue. (2) High submaximal HR — the same workout at the same pace shows higher HR than your baseline. (3) Low HRV — reduced heart rate variability measured each morning indicates autonomic nervous system stress. (4) Inability to reach Zone 4–5 — paradoxically, severely overtrained athletes often cannot achieve high heart rates despite maximal effort, known as parasympathetic overtraining. (5) Prolonged post-exercise HR elevation — heart rate stays elevated much longer than normal after completing a workout. Track resting HR daily; consistent elevation over 3+ consecutive days warrants a significant reduction in training load.
Should I train by heart rate or pace?+
Both metrics have value in different contexts. Heart rate training is superior when conditions vary (heat, altitude, fatigue, wind), when you want to match physiological effort rather than external output, and during easy aerobic base-building sessions to prevent drifting into Zone 3. Pace training is better when preparing for a goal race time, when comparing training performances across identical conditions, and for structured interval sessions where split times matter directly. Most experienced athletes use both: heart rate for easy Zone 2 sessions to prevent intensity creep, pace or power for threshold and interval sessions. One important caveat: heart rate lags effort by 60–90 seconds, making it less useful for very short intervals under 3 minutes.
How do I build a Zone 2 aerobic base?+
To build an aerobic base, commit to 3–5 Zone 2 sessions per week for 8–12 weeks. Keep your heart rate in 60–70% HRR — a truly conversational pace where you can comfortably hold a full sentence. Many trained athletes discover their required pace for Zone 2 is far slower than expected; this is completely normal and reflects an underdeveloped aerobic base. Resist the urge to push harder. Increase weekly volume by no more than 10% each week (the "10% rule"). Use low-impact modalities like cycling, elliptical, or swimming if slow running causes joint stress. The clearest sign of aerobic base improvement: your pace at any given heart rate progressively improves over weeks — you run faster at the same HR. Resting HR also noticeably decreases after 6–8 weeks of consistent Zone 2 training.
What is heart rate variability (HRV) and how do I use it?+
Heart rate variability measures the millisecond variation in time between consecutive heartbeats. Counterintuitively, higher HRV indicates better health — a responsive, flexible autonomic nervous system. Low HRV signals chronic stress, accumulated training fatigue, illness, or poor sleep. During quality recovery sleep, parasympathetic activity dominates and HRV is high. During overtraining or illness, sympathetic activation dominates and HRV drops. Modern wearables including Whoop, Garmin, and Apple Watch measure HRV each morning. Use it as a readiness guide: when HRV is higher than your 7-day baseline, you are well-recovered and can handle intense training; when it is lower than baseline for multiple days consecutively, prioritize easy Zone 1–2 sessions or complete rest before returning to hard training.
Can older adults still train in all 5 heart rate zones?+
Yes, with appropriate modifications. As age increases, max HR declines roughly 1 bpm per year, recovery between hard sessions takes longer (48–72 hours vs 24 hours for younger athletes), and injury risk from high-intensity work increases. Older adults benefit from prioritizing Zone 2 training for its longevity-supporting mitochondrial benefits, allowing adequate recovery time between Zone 4–5 sessions, and including strength training alongside cardio to preserve muscle mass. Research on masters athletes consistently shows Zone 2 training preserves cardiovascular capacity and metabolic health through the sixth, seventh, and eighth decades of life. The Karvonen formula automatically accounts for resting HR changes with age, making it especially well-suited for older adults compared to simple percentage-of-max calculations.
How long should each zone training session be?+
Optimal session lengths differ by zone: Zone 1 (Recovery): 20–60 minutes; used as active rest between hard training days. Zone 2 (Endurance): 45–180+ minutes; the aerobic foundation — benefits compound with greater weekly volume. Zone 3 (Tempo): 20–60 minutes; use sparingly, research suggests minimizing Z3 for best adaptation outcomes. Zone 4 (Threshold): intervals of 10–20 minutes or continuous 20–40 minutes; limit to 1–2 sessions per week maximum. Zone 5 (VO₂ Max): 3–8 minute work intervals with equal-length rest; total work time 15–30 minutes per session; 1 session per week maximum for most recreational athletes. Never perform consecutive hard Zone 4–5 sessions without at least one Zone 1–2 recovery day between them to allow adaptation and prevent overtraining.
Does caffeine affect heart rate zone accuracy?+
Yes, caffeine substantially raises heart rate at rest and during exercise. A 200–400 mg dose (1–2 cups of coffee or a pre-workout) raises exercise HR by 5–10 bpm at the same effort level by blocking adenosine receptors and stimulating catecholamine release. This creates a mismatch: your heart rate is elevated above what the actual physiological output warrants, meaning you are working less hard than your HR suggests. For consistent zone training, either always train with the same caffeine status so your zones remain calibrated to your normal state, train without caffeine to establish an accurate uncaffeinated baseline, or mentally adjust your zone targets upward by 5–8 bpm on caffeinated training days. Pre-workout supplements often contain 150–300 mg caffeine, creating significant HR inaccuracy for zone-based training.

References & Further Reading

  • • Karvonen, M.J., Kentala, E., & Mustala, O. (1957). The effects of training on heart rate. Annales Medicinae Experimentalis et Biologiae Fenniae.
  • • Tanaka, H., Monahan, K.D., & Seals, D.R. (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology, 37(1).
  • • Seiler, S., & Kjerland, G.Ø. (2006). Quantifying training intensity distribution in elite endurance athletes. Scandinavian Journal of Medicine & Science in Sports, 16(1).
  • • Robergs, R.A., & Landwehr, R. (2002). The surprising history of the HRmax=220−age equation. Journal of Exercise Physiology, 5(2).
  • • American Heart Association. (2021). Target Heart Rates Chart. heart.org
  • • American College of Sports Medicine. (2018). ACSM's Guidelines for Exercise Testing and Prescription, 10th edition.
  • • San Millan, I., & Brooks, G.A. (2018). Assessment of metabolic flexibility by means of measuring blood lactate. Frontiers in Physiology.

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Heart Rate Calculator — Complete Guide

Target heart rate zones, Karvonen formula, VO₂max estimation, training zone science, and resting HR norms.

5

Training heart rate zones

220−Age

Max HR estimate formula

40–100

Normal resting HR (bpm)

60–70%

Fat-burning zone threshold

What Is Target Heart Rate?

Target heart rate (THR) is the range of beats per minute (bpm) that corresponds to a desired exercise intensity. Training within specific heart rate zones allows you to match exercise intensity to fitness goals — whether that is fat burning, aerobic base building, anaerobic threshold training, or peak power development.

Heart rate is a proxy for oxygen consumption and energy expenditure. At higher intensities, the heart beats faster to deliver more oxygenated blood to working muscles. Because the relationship between HR and oxygen consumption (VO₂) is nearly linear between 50–90% of maximum effort, heart rate provides a reliable, real-time indicator of exercise intensity without requiring laboratory equipment.

The American Heart Association (AHA) recommends targeting 50–85% of maximum heart rate for cardiovascular health benefits. The exact zone you train in determines the metabolic fuel used, the physiological adaptations achieved, and the recovery required between sessions.

Maximum Heart Rate Formulas

Classic Formula (Fox 1971)
Max HR = 220 − Age

Examples:
  Age 20: Max HR = 200 bpm
  Age 30: Max HR = 190 bpm
  Age 40: Max HR = 180 bpm
  Age 50: Max HR = 170 bpm
  Age 60: Max HR = 160 bpm
  Age 70: Max HR = 150 bpm

Limitations:
  • Standard deviation: ±10–12 bpm
  • Underestimates max HR for
    fit/athletic older adults
  • Original dataset was small and
    not peer-reviewed by Fox himself
  • Still the most widely used estimate
    due to simplicity

Bottom line: reliable for population
averages, not individual prescriptions.

The 220−age formula was never derived from a study per se — Fox cited it informally in 1971. Despite this, it remains the clinical standard because it is easy to use and accurate enough for most purposes.

Tanaka Formula (More Accurate)
Max HR = 208 − (0.7 × Age)

(Tanaka H et al., J Am Coll Cardiol. 2001)

Based on 351 studies, 18,712 subjects
R² = 0.90 with measured max HR

Examples:
  Age 20: 208 − 14 = 194 bpm
  Age 30: 208 − 21 = 187 bpm
  Age 40: 208 − 28 = 180 bpm
  Age 50: 208 − 35 = 173 bpm
  Age 60: 208 − 42 = 166 bpm
  Age 70: 208 − 49 = 159 bpm

Advantages:
  • More accurate than 220−age formula
  • Based on large diverse meta-analysis
  • Better for older adults (>40 years)
  • Lower error at older ages

The Tanaka formula is statistically superior to 220−age and is increasingly recommended in clinical exercise prescription, especially for adults over 40 who are regularly active.

Karvonen Formula (Personalised)
THR = [(MaxHR − RHR) × Intensity%] + RHR

Where RHR = Resting Heart Rate

Example (30y man, RHR 60, target Zone 3 70%):
  Max HR = 220 − 30 = 190 bpm
  HRR = 190 − 60 = 130 bpm
  THR = (130 × 0.70) + 60
  THR = 91 + 60 = 151 bpm

Zone 3 range (70–80%):
  Lower = (130 × 0.70) + 60 = 151 bpm
  Upper = (130 × 0.80) + 60 = 164 bpm

Why Karvonen is superior:
  Accounts for cardiovascular fitness
  (lower RHR = larger heart rate reserve)
  Gives more precise individual targets

The Karvonen formula uses Heart Rate Reserve (HRR = MaxHR − RHR). Athletes with a low resting HR have a larger HRR, meaning their zone targets are at higher absolute bpm — correctly reflecting their fitness.

VO₂max Estimation from HR
Simple HR ratio estimate:
VO₂max ≈ 15 × (MaxHR ÷ RHR)
(Uth 2004 — accurate to ±10%)

Example (MaxHR 185, RHR 55):
VO₂max ≈ 15 × (185 ÷ 55)
VO₂max ≈ 15 × 3.36
VO₂max ≈ 50.5 ml/kg/min

VO₂max classifications for men:
  <35  Poor
  35–42  Fair
  43–52  Good
  53–60  Excellent
  >60  Superior / Athletic

VO₂max classifications for women:
  <27  Poor
  27–35  Fair
  36–45  Good
  46–53  Excellent
  >53  Superior / Athletic

VO₂max is the gold standard measure of cardiovascular fitness. This HR-ratio estimate is convenient but laboratory treadmill testing (Bruce protocol) or submaximal tests (Cooper 12-min run) are more accurate.

The 5 Heart Rate Training Zones

ZoneName% Max HRHR at Age 40Primary FuelBest For
1Active Recovery50–60%90–108 bpmFat (>85%)Recovery, warm-up, beginners
2Aerobic Base60–70%108–126 bpmFat (65%)Endurance, fat loss foundation
3Aerobic Endurance70–80%126–144 bpmMixed (50/50)Cardiovascular fitness building
4Threshold / Tempo80–90%144–162 bpmCarbs (>65%)Lactate threshold, race pace
5Maximum / VO₂max90–100%162–180 bpmCarbs (>85%)Peak power, HIIT, sports

Frequently Asked Questions

What is a normal resting heart rate?▼

For adults, a normal resting heart rate is 60–100 bpm. Highly trained athletes often have resting HR of 40–60 bpm. A consistently elevated resting HR (>100 bpm at rest) is called tachycardia and warrants medical evaluation. A very low resting HR (<40 bpm) in non-athletes may also need assessment.

How do I measure my resting heart rate?▼

Measure resting HR first thing in the morning, before getting out of bed or drinking coffee. Use your index and middle finger on the radial pulse (wrist, thumb side) or carotid artery (neck). Count for 60 seconds for accuracy. Take the average over 3 consecutive mornings.

Is it dangerous to exercise at 100% of max HR?▼

Brief periods at or near max HR are not dangerous for healthy adults with no cardiac contraindications. However, sustained maximal effort is only appropriate for fit individuals. Always get medical clearance before starting high-intensity training if you have a history of heart disease, hypertension, or are over 50 and sedentary.

References & Clinical Sources

  • Tanaka H, et al. Age-predicted maximal heart rate revisited. J Am Coll Cardiol. 2001;37(1):153–6.
  • Karvonen J, Vuorimaa T. Heart rate and exercise intensity during sports activities. Sports Med. 1988;5(5):303–11.
  • American Heart Association. Target Heart Rates Chart. AHA, 2023.
  • Uth N, et al. Estimation of VO2max from the ratio between HRmax and HRrest. Eur J Appl Physiol. 2004;91(1):111–5.
Calories Burned CalculatorVO₂max / Pace CalculatorTDEE CalculatorOne Rep Max Calculator

See Also

Pace Calculator

Match your running pace to target heart rate zones.

Calories Burned Calculator

Heart rate zone determines how many calories you burn.

TDEE Calculator

Exercise heart rate affects your total daily energy expenditure.