Maximum heart rate
The popular "220 − age" formula is easy but imprecise. The Tanaka formula (208 − 0.7 × age) was derived from a much larger set of studies and is usually closer. Both are averages: a real person can be 10–20 beats above or below. A supervised exercise test gives your true maximum.
Karvonen method
When you enter your resting heart rate, zones are based on your heart rate reserve (max − resting): target = resting + reserve × intensity. This adjusts the zones to your fitness level.
The five zones
Zone 2 (easy, conversational) builds endurance and should make up most training time for many people. Zones 4–5 are for short, hard intervals.
Frequently asked questions
I take blood pressure medication. Do these zones apply?
Possibly not. Beta-blockers and some other medicines lower heart rate. Ask your doctor for personal targets.
How do I measure resting heart rate?
In the morning before getting up, count your pulse for 60 seconds, or use the average from a fitness watch over several days.
Is it safe to train in zone 5?
For healthy people, short efforts are fine. If you have heart disease or symptoms such as chest pain, get medical clearance first.