Long-distance triathlon glossary·FCR

Heart Rate Reserve : Karvonen method

Load

The range between resting HR and max HR, used to calculate more personalised HR zones.

HR Reserve = max HR − resting HR. The Karvonen method derives intensity zones across this range: Z1 at 50-60% HRR, Z2 at 60-70%, Z4 at 80-90%. It is more accurate than raw % max HR because it accounts for fitness level. An athlete with a resting HR of 45 bpm and a max HR of 185 bpm has an HRR of 140 bpm : a wider usable range.

In TriPaced:

In TriPaced, if you enter both max HR and resting HR in Settings, zones are computed via Karvonen. Without resting HR, the default method (direct % max HR) is used.

Related terms

  • TSS : Training Stress Score
  • CTL : Chronic Training Load (fitness)
  • ATL : Acute Training Load (fatigue)
  • TSB : Training Stress Balance (freshness)
  • Sweet spot : the efficiency zone
  • Threshold : the upper sustainable limit