Health

Heart Rate Zone

Definition

Ranges of heart rate intensity during exercise, expressed as percentages of maximum heart rate, used to optimize training for specific fitness goals.

Formula

Max Heart Rate (estimated) = 220 - age

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Heart rate zones divide exercise intensity into five ranges based on percentages of your maximum heart rate (MHR). Zone 1 (50-60% MHR) is light recovery, Zone 2 (60-70%) builds endurance, Zone 3 (70-80%) improves aerobic capacity, Zone 4 (80-90%) increases threshold, and Zone 5 (90-100%) is maximum effort.

Training in different zones targets different physiological adaptations. Zone 2 training, often called the fat-burning zone, is where the body uses the highest percentage of fat for fuel. Higher zones improve cardiovascular performance, lactate threshold, and VO2 max but are more demanding on the body.

Most fitness experts recommend spending 80% of training time in Zones 1-2 and only 20% in Zones 3-5, known as the 80/20 polarized training approach. This balanced approach builds a strong aerobic base while including enough high-intensity work to drive performance improvements without overtraining.

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