How this calculation works
The Target Heart Rate (THR) Calculator computes the precise beats-per-minute (BPM) range to maintain during exercise to achieve specific fat loss, aerobic fitness, and cardiovascular endurance goals.
Mathematical formula and logic
Heart Rate Reserve (HRR) = Max HR - Resting HR. Target Heart Rate Range = (HRR × Low %) + Resting HR to (HRR × High %) + Resting HR.
Worked example
For a 40-year-old with a resting HR of 65 bpm aiming for vigorous aerobic exercise (70-85%): Target heart rate range is 145 to 163 BPM.
Calculation assumptions
- Karvonen Heart Rate Reserve methodology for individualized conditioning.
- American Heart Association (AHA) target exercise intensity thresholds.
Frequently asked questions
What is a safe target heart rate during exercise?
The American Heart Association generally recommends exercising within 50% to 85% of your maximum heart rate for safe cardiovascular conditioning.
How long should I stay in my target heart rate zone?
Aim for at least 20 to 30 continuous minutes within your target aerobic heart rate zone, 3 to 5 days per week.
Why is resting heart rate important in the Karvonen formula?
Fitter athletes have lower resting heart rates (larger stroke volume). The Karvonen formula accounts for individual baseline fitness by calculating Heart Rate Reserve (HRmax - HRrest).
Can medications affect my target heart rate?
Yes, beta-blockers and blood pressure medications lower resting and exercise heart rates. Consult your doctor for modified perceived-exertion (RPE) guidelines.
What should I do if my heart rate exceeds the target zone?
Slow your running pace, reduce cycling resistance, or switch to brisk walking until your pulse returns to your prescribed target range.