Target Heart Rate
Calculate your target heart rate zones for training.
Heart rate training uses your heart rate as a guide to control exercise intensity. By monitoring your heart rate during workouts, you can ensure you're training at the right intensity for your goals—whether that's burning fat, building endurance, or improving speed.
The five heart rate zones range from very light (Zone 1) to maximum effort (Zone 5). Each zone targets different energy systems and produces specific adaptations in your body.
The Karvonen formula calculates target heart rate using Heart Rate Reserve (HRR)—the difference between your maximum and resting heart rates. This provides more accurate zones than simple percentage-of-max calculations.
Target HR = ((Max HR - Resting HR) × % Intensity) + Resting HR
By accounting for resting heart rate, the Karvonen method gives personalized zones that reflect your current fitness level. A well-trained athlete with a low resting HR will have different absolute zone values than a beginner.
Zone 2: The Fat Burning Sweet Spot
Zone 2 training builds your aerobic base, improves fat oxidation, and can be sustained for long periods. It's the foundation of endurance and should make up the majority of training volume.
Zone 4-5: High Intensity Training
Higher zones improve VO2 max, lactate threshold, and speed. Use sparingly (1-2 times per week) as they require significant recovery time.
Frequently Asked Questions
Target Heart Rate (THR) is the ideal heart rate range for effective exercise. Training within your target zones ensures you're working hard enough to improve fitness while not overexerting yourself.
Measure your pulse first thing in the morning, before getting out of bed. Count beats for 60 seconds, or count for 15 seconds and multiply by 4. Take measurements over several days and use the average.
Heart Rate Reserve (HRR) is the difference between your maximum heart rate and resting heart rate. The Karvonen formula uses HRR to calculate more accurate training zones that account for your individual fitness level.
It depends on your goals. Zone 2 (60-70%) is best for fat burning and endurance. Zone 3-4 (70-90%) improves cardiovascular fitness. Zone 5 (90-100%) is for high-intensity intervals. Most people benefit from spending 80% of training time in Zone 2-3.
The 220-age formula is a rough estimate with ±10-12 bpm variation. The Tanaka formula (208 - 0.7 × age) is more accurate. For the most precise max HR, do a supervised maximal exercise test or use your highest recorded heart rate during all-out effort.
A lower resting heart rate indicates a stronger, more efficient heart. Trained athletes often have resting heart rates of 40-60 bpm compared to 60-100 bpm for untrained individuals. The heart pumps more blood per beat, so it needs fewer beats.
Health Notice
These heart rate zones are estimates. Individual variation can be significant (±10-12 bpm for max HR predictions). If you have any cardiovascular conditions, take medications that affect heart rate, or are new to exercise, consult your doctor before starting a training program.