Target Heart Rate Calculator - Calculate Training Heart Rate Zones by Age
Heart Rate Information
Default: 70 bpm (average adult). Measure first thing in the morning before getting out of bed.
How to measure resting heart rate:
- • Measure first thing in the morning
- • Before getting out of bed
- • Count pulse for 60 seconds
- • Use wrist or neck pulse point
Enter your information and click "Calculate Heart Rate Zones" to see your personalized training zones
Understanding Target Heart Rate Training
What is Target Heart Rate?
Target heart rate (THR) is the ideal range your heart should beat during exercise to achieve specific training benefits while staying safe. Training at different heart rate intensities produces different physiological adaptations:
- Zone 1-2 (50-70%): Fat oxidation, aerobic base building, recovery
- Zone 3 (70-80%): Cardiovascular fitness, aerobic capacity, endurance
- Zone 4 (80-90%): Lactate threshold, speed, anaerobic capacity
- Zone 5 (90-100%): Maximum power, VO2 max, neuromuscular training
The American Heart Association recommends exercising at 50-85% of maximum heart rate for cardiovascular benefits. Beginners should start at 50-70% and gradually increase intensity as fitness improves. Visit the American Heart Association for official guidelines on target heart rate training.
Maximum Heart Rate Formula
220 - Age = Max HR
This simple formula is widely used and validated by the American College of Sports Medicine. While individual variation exists (±10-15 bpm), it provides a safe and effective estimate for most adults.
Example: A 30-year-old has a maximum heart rate of approximately 190 bpm (220 - 30 = 190). This means their heart should not exceed 190 beats per minute during maximum effort exercise.
Karvonen Formula (More Accurate)
Target HR = (HRR × %Intensity) + Resting HR
HRR = Max HR - Resting HR
The Karvonen formula accounts for individual fitness by using heart rate reserve (HRR). Athletes with low resting heart rates get more personalized zones than the simple percentage method.
Example: 30-year-old, 60 bpm resting HR, targeting 70% intensity: HRR = 190-60 = 130. Target HR = (130 × 0.70) + 60 = 151 bpm.
The Five Heart Rate Training Zones Explained
Zone 1: Warm-up (50-60% Max HR)
Purpose: Warm-up, cool-down, active recovery. Very comfortable pace where conversation is easy and natural.
Benefits: Increases blood flow, prepares muscles for exercise, promotes recovery, helps beginners build exercise tolerance.
Examples: Gentle walking, easy cycling, light swimming. Use before and after harder workouts, or on recovery days.
Zone 2: Fat Burning (60-70% Max HR)
Purpose: Aerobic base building, fat metabolism, endurance foundation. Can maintain conversation in full sentences.
Benefits: Maximizes fat oxidation, builds aerobic capacity, improves metabolic efficiency, sustainable for long durations (45-120 minutes). This is where most endurance athletes spend 70-80% of training time.
Examples: Steady jogging, moderate cycling, brisk walking. The "all-day pace" where you could theoretically continue for hours.
Zone 3: Aerobic (70-80% Max HR)
Purpose: Cardiovascular fitness, aerobic capacity development. Breathing harder, can speak in short sentences but not comfortably.
Benefits: Improves cardiovascular fitness, increases VO2 max, strengthens heart muscle, builds endurance for longer efforts. This is "tempo" pace for many athletes.
Examples: Tempo runs, steady-state cycling, vigorous swimming. Sustainable for 20-60 minutes depending on fitness level.
Zone 4: Anaerobic (80-90% Max HR)
Purpose: Lactate threshold training, speed development, anaerobic capacity. Very hard effort, can only speak a few words.
Benefits: Increases lactate threshold (ability to sustain hard effort), improves speed, develops anaerobic capacity, enhances performance. Builds mental toughness.
Examples: Interval training (4×5 minutes hard with 3-minute recovery), race pace for 5K-10K, hill repeats. Limited to 20-40 minutes total time in zone.
Zone 5: Maximum Effort (90-100% Max HR)
Purpose: Maximum power output, VO2 max development, neuromuscular training. Cannot speak, maximum sustainable effort for short periods.
Benefits: Increases VO2 max (maximum oxygen uptake), develops maximum power, improves neuromuscular coordination, mental resilience. Used sparingly due to high stress and long recovery needs.
Examples: Sprint intervals (30 seconds to 2 minutes), racing finish kicks, all-out efforts. Limited to 5-15 minutes total per week for most athletes.
How to Apply Heart Rate Training to Your Workouts
Beginner Training Plan (First 4-6 Weeks)
- •Monday/Wednesday/Friday: 20-30 minutes Zone 2 (60-70%) - Build aerobic base
- •Tuesday/Thursday: Rest or Zone 1 (50-60%) active recovery - 15-20 minutes
- •Saturday: 30-45 minutes Zone 2 (60-70%) - Long easy workout
- •Sunday: Complete rest or gentle Zone 1 walking
Focus: Build aerobic base and exercise habit before adding intensity. Stay in Zones 1-2 exclusively.
Intermediate Training Plan (After 2-3 Months)
- •Monday: 30-45 minutes Zone 2 (60-70%) easy aerobic
- •Tuesday: Zone 4 intervals (80-90%) - 6×3 minutes hard, 2 minutes easy recovery
- •Wednesday: 30-40 minutes Zone 2 (60-70%) recovery
- •Thursday: 25-30 minutes Zone 3 (70-80%) tempo
- •Friday: Rest or 20-30 minutes Zone 1 (50-60%)
- •Saturday: 60-75 minutes Zone 2 (60-70%) long run/ride
- •Sunday: Rest or easy Zone 1 activity
Focus: 80/20 rule - 80% easy/moderate (Zones 1-3), 20% hard (Zones 4-5). Build speed while maintaining aerobic base.
Advanced Training Plan (Experienced Athletes)
- •Monday: 45-60 minutes Zone 2 (60-70%) + 4×30 sec Zone 5 strides
- •Tuesday: Zone 4-5 VO2 max intervals - 5×3 min at 90-95%, 3 min recovery
- •Wednesday: 40-50 minutes Zone 2 recovery with 10 min Zone 3
- •Thursday: Zone 4 threshold - 2×15 min at 80-85%, 5 min recovery
- •Friday: 30-40 minutes Zone 1-2 easy
- •Saturday: 90-120 minutes Zone 2 long endurance with 20 min Zone 3
- •Sunday: 45-60 minutes Zone 1-2 active recovery or rest
Focus: Periodized training with specific adaptations. Still follows 80/20 principle but with more sophisticated interval structures.
Heart Rate Monitoring: Tools and Tips
📱Chest Strap Monitors (Most Accurate)
Accuracy: 95-99% (EKG-level accuracy)
How it works: Measures electrical signals from heartbeats, same technology as medical EKG.
Best for: Serious training, interval workouts, accurate zone training, high-intensity exercise.
Popular models: Polar H10, Garmin HRM-Pro, Wahoo TICKR X. Typically $50-100.
⌚Wrist-Based Optical Sensors
Accuracy: 85-95% (varies by conditions)
How it works: Uses LED lights to detect blood flow changes under the skin.
Best for: General fitness tracking, all-day monitoring, convenient everyday use, moderate-intensity exercise.
Limitations: Less accurate during high-intensity intervals, arm movements, cold weather. Affected by skin tone, tattoos, and fit.
Tips for Accurate Heart Rate Monitoring
- 1.Chest straps: Wet the electrodes before use, ensure snug fit (1-2 fingers can fit), worn just below chest muscles.
- 2.Wrist sensors: Wear 1-2 finger widths above wrist bone, snug but not tight, keep arm steady during readings.
- 3.Warm-up effect: Heart rate may lag 1-2 minutes when intensity changes. Be patient when entering new zones.
- 4.Environmental factors: Heat/humidity increases HR by 10-20 bpm, altitude by 5-15 bpm. Adjust zones accordingly.
- 5.Update resting HR monthly: As fitness improves, resting HR decreases. Recalculate zones every 4-6 weeks.
⚠️ Important Safety Considerations
When to Consult a Doctor Before Exercise
- • Resting heart rate consistently above 100 bpm or below 40 bpm (unless trained athlete)
- • History of heart disease, high blood pressure, or cardiovascular conditions
- • Chest pain, dizziness, or shortness of breath during or after exercise
- • Irregular heartbeat or palpitations during physical activity
- • Taking medications that affect heart rate (beta-blockers, etc.)
- • Age over 40 (men) or 50 (women) starting vigorous exercise program
- • Chronic health conditions: diabetes, asthma, arthritis, kidney disease
Warning Signs to Stop Exercise Immediately
- • Chest pain or pressure (especially radiating to arm, jaw, or back)
- • Severe shortness of breath that doesn't improve with rest
- • Dizziness, lightheadedness, or feeling faint
- • Irregular or racing heartbeat that feels abnormal
- • Nausea or vomiting during exercise
- • Confusion or inability to focus
- • Cold sweats or unusual fatigue
If you experience any of these symptoms, stop exercising immediately and seek medical attention if symptoms persist.
Medications That Affect Heart Rate
Several medications can significantly affect heart rate during exercise. If you take any of these, consult your doctor before using target heart rate training:
- • Beta-blockers (for high blood pressure, heart conditions) - Lower max heart rate by 20-30 bpm
- • Calcium channel blockers - May reduce heart rate response to exercise
- • Antidepressants (SSRIs, TCAs) - Can affect heart rate variability
- • Stimulants (ADHD medications) - Increase resting and exercise heart rate
- • Thyroid medications - Affect metabolic rate and heart rate
Your doctor can help adjust your target heart rate zones or recommend alternative intensity measures like Rate of Perceived Exertion (RPE).
Frequently Asked Questions
What is target heart rate and why is it important?
Target heart rate is the ideal range your heart should beat during exercise for maximum cardiovascular benefit and safety. It ensures you're exercising at the right intensity - not too easy (ineffective) or too hard (potentially dangerous). Training in different heart rate zones produces specific benefits: Zone 2 (60-70%) burns fat efficiently, Zone 3 (70-80%) improves cardiovascular fitness, and Zone 4 (80-90%) builds speed and power. Monitoring your heart rate helps optimize workouts, track fitness improvements, and prevent overtraining.
How do I calculate my target heart rate zones?
The most accurate method is the Karvonen formula: (Max HR - Resting HR) × %Intensity + Resting HR. First, calculate your maximum heart rate (220 - age). Then subtract your resting heart rate (measured first thing in the morning) to get your heart rate reserve (HRR). Multiply HRR by the intensity percentage (e.g., 0.70 for 70%) and add back your resting heart rate. For example, a 30-year-old with 70 bpm resting HR: Max HR = 190, HRR = 120. Zone 3 (70-80%) would be 154-166 bpm.
What is the difference between the Karvonen formula and the simple percentage method?
The simple percentage method (Max HR × percentage) doesn't account for individual fitness levels. The Karvonen formula is more accurate because it uses heart rate reserve (Max HR - Resting HR), which adjusts for your fitness level. Athletes with low resting heart rates (50-60 bpm) get more personalized zones than using just maximum heart rate. For a 30-year-old with 60 bpm resting HR: simple method gives Zone 3 as 133-152 bpm, while Karvonen gives 151-165 bpm - a significant difference that better reflects their fitness level.
Which heart rate zone is best for fat burning?
Zone 2 (60-70% of max heart rate) is the classic "fat burning zone" where your body primarily uses fat for fuel. However, higher intensity zones (3-4) burn more total calories, including significant fat calories. For weight loss, the best strategy is mixing both: 70-80% of weekly cardio in Zone 2 for building aerobic base and fat oxidation, plus 20-30% in Zones 3-4 for higher calorie burn. Zone 2 training is also sustainable for longer durations (45-90 minutes), maximizing total fat burned.
How accurate are heart rate monitors and fitness trackers?
Chest strap heart rate monitors are most accurate (95-99% accuracy), using electrical signals like an EKG. Wrist-based optical sensors (like Apple Watch, Garmin, Fitbit) are 85-95% accurate at rest but can be less accurate during high-intensity exercise, especially with arm movement. Factors affecting wrist sensors: skin tone, tattoos, tight/loose fit, cold temperatures, and arm position. For serious training, use a chest strap. For general fitness tracking, wrist sensors are adequate. Manual pulse checking (60-second count) is reliable if done correctly.
When should I train in different heart rate zones?
Structure your weekly training using the 80/20 rule: 80% easy (Zones 1-2) and 20% hard (Zones 4-5). Monday/Wednesday/Friday: 30-60 minutes Zone 2 (aerobic base building). Tuesday: Zone 4 intervals (4×5 minutes at 80-90% with 3-minute rest). Thursday: Zone 3 tempo run (20-30 minutes at 70-80%). Saturday: Long Zone 2 session (60-90 minutes). Sunday: Zone 1 active recovery or rest. This balance builds endurance without overtraining. Beginners should spend 4-6 weeks in Zones 1-2 before adding high-intensity work.