How heart rate zone training works

Training by heart rate lets you target effort levels precisely, rather than guessing from pace alone — useful on hilly routes, in heat, or when fatigue affects your normal pace. The Karvonen method (using heart rate reserve, the gap between resting and max HR) is generally considered more accurate than a simple percentage of max, since it accounts for your individual fitness rather than age alone.

• Zone 1 — Recovery. Easy jogs and warm-ups, conversation is effortless.
• Zone 2 — Easy / aerobic. Long runs and easy mileage, builds your aerobic base.
• Zone 3 — Tempo. Steady, comfortably hard effort.
• Zone 4 — Threshold. Sustained hard effort near lactate threshold.
• Zone 5 — VO2 max. Short, hard intervals for top-end speed.

Want a personalised training plan built around your own zones? Take a look at bespoke training plans or online coaching, or get in touch for a free, no-pressure chat.