1. What is Heart Rate Reserve?

Heart Rate Reserve (HRR) is the difference between your maximum heart rate and resting heart rate. It represents the full range of heart rate response available to your body for physical activity.

2. How Does the Calculator Work?

The calculator uses the simple HRR formula:

Where:

• Max HR — Maximum heart rate (beats per minute)
• Resting HR — Resting heart rate (beats per minute)

Explanation: HRR indicates your heart's capacity to respond to exercise demands. A higher HRR typically indicates better cardiovascular fitness.

3. Importance of HRR Calculation

Details: HRR is used to calculate exercise intensity zones (like 50-85% of HRR) and is a key component in the Karvonen formula for personalized training.

4. Using the Calculator

Tips: Enter your maximum heart rate (measured or estimated as 220-age) and resting heart rate (measured first thing in the morning). Both values must be valid positive numbers with max HR > resting HR.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure my maximum heart rate?
A: The most accurate way is through a graded exercise test. The "220-age" formula is an estimate that may vary by ±10-20 bpm.

Q2: When should I measure resting heart rate?
A: Measure first thing in the morning while still in bed, before any activity or caffeine.

Q3: What's a normal HRR value?
A: Typical values range from 60-100 bpm. Higher values generally indicate better cardiovascular fitness.

Q4: How is HRR used in exercise training?
A: HRR helps determine target heart rate zones (e.g., 60-80% of HRR plus resting HR for moderate exercise).

Q5: Does HRR change with fitness level?
A: Yes, as you become more fit, your resting HR typically decreases, increasing your HRR.