What Are Heart Rate Zones?

Heart Rate Zones divide your cardiac effort into 5 distinct training areas, each producing different physiological adaptations.

The 5 Zones Explained

How to Calculate Your Zones

Method 1: Max Heart Rate Formula

Max HR = 220 - Age (rough estimate)
Max HR = 208 - (0.7 × Age) (more accurate)

Method 2: Heart Rate Reserve (Karvonen)

Target HR = ((Max HR - Resting HR) × %) + Resting HR

Method 3: Lactate Threshold Test

The gold standard — requires lab testing or field test.

Zone Training for Runners

Easy/Recovery Days (Z1-Z2)

• Long runs
• Recovery runs
• Should be 80% of your training

Tempo/Threshold (Z4)

• Tempo runs
• "Comfortably hard"
• Improves lactate clearance

Speed Work (Z5)

• Intervals
• Short bursts
• Builds VO2max

Common Mistakes

❌ Running Z2 runs in Z3 (too fast)
❌ Not going hard enough on hard days
❌ Using only pace (ignoring HR data)
❌ Not accounting for heat, altitude, fatigue

Zone 2 Magic

Elite runners spend 80% of their training in Zone 2:

• Builds mitochondria
• Improves fat oxidation
• Enables high training volume
• Allows proper recovery

Tools for HR Training

• GPS watches: Garmin, Polar, COROS
• Chest straps: Most accurate
• Optical sensors: Convenient but less precise

Pro tip: Your zones are personal — what's Z2 for you might be Z3 for someone else!