Heart rate zones give every training session a physiological purpose. Based on your individual resting and maximum heart rate, the Karvonen method calculates personalised zones that reflect your actual working range — not generic population averages.
Use these zones to guide intensity across swim, bike and run sessions, and to ensure your easy days are genuinely easy and your hard days hard. That balance is what drives adaptation.
| Zone | % HRR | BPM range |
|---|
Heart rate training is most effective when zones are applied intelligently within a structured programme — knowing when to sit in zone 2 for an hour, when to push into zone 4 for threshold intervals, and when to go to the well in zone 6. Our coaches build programmes that use HR as one of several tools to drive consistent, progressive improvement.
Talk to a coachNo obligation — just a conversation about where you are and where you want to get to.
Karvonen et al. (1957) Ann Med Exp Biol Fenn 35(3). Zone structure adapted from Friel (2009) and Seiler & Tønnessen (2009).