Using the Karvonen Formula (Heart Rate Reserve method) for higher accuracy.
Zone
Intensity
Heart Rate (BPM)
Benefit
How to Use Heart Rate Zones to Improve Your Running
Training by heart rate is one of the most effective ways for runners to ensure they are working at the right intensity. Instead of relying on perceived exertion, which can be influenced by weather, sleep, or stress, heart rate zones provide objective data to guide your workouts.
Understanding the Karvonen Formula
This calculator uses the Karvonen Formula. Unlike simple percentage-of-max-HR calculations, the Karvonen method incorporates your Resting Heart Rate (RHR) to calculate your Heart Rate Reserve (HRR). This provides a more personalized set of zones because it accounts for your current cardiovascular fitness level.
The Five Running Zones Explained
Zone 1 (50-60% HRR): Very Light. Best for recovery runs and warming up. It improves overall health and helps recovery after harder sessions.
Zone 2 (60-70% HRR): Light (The "Base" Zone). This is where you build endurance. Most of your weekly mileage should be in Zone 2. It enhances the body's ability to burn fat and builds aerobic capacity.
Zone 3 (70-80% HRR): Moderate. Often called "Aerobic" or "Marathon Pace." It improves aerobic power and is excellent for building efficiency for long-distance events.
Zone 4 (80-90% HRR): Hard (Threshold). This is your anaerobic threshold. Training here improves your body's ability to handle lactic acid, allowing you to run faster for longer.
Zone 5 (90-100% HRR): Maximum. Reserved for interval training and sprints. This improves your VO2 max and top-end speed.
Example Calculation
If a 40-year-old runner has a resting heart rate of 60 BPM: