Heart Rate Reserve (HRR)
What is Heart Rate Reserve (HRR)?
Heart rate reserve (HRR) = maximum heart rate minus resting heart rate. For example, if your max HR is 190 and resting HR is 50, your HRR is 140 bpm. HRR is used in the Karvonen formula to calculate individualised training zones: Target HR = resting HR + (intensity % × HRR). This method is more accurate than simple percentage-of-max-HR calculations because it accounts for individual cardiac fitness — a person with a low resting HR has a larger functional range. HRR-based zones are the standard in rowing training prescription and are used by most structured rowing programmes.
How Watta Uses Heart Rate Reserve (HRR)
Watta uses the Karvonen method (HRR-based) to calculate heart rate zones and the Cardiac Load component of the Effort Score. When you provide your max HR and resting HR, the algorithm uses HRR to determine intensity zones and apply non-linear scaling to the cardiac load calculation (40% of total score).
Further Reading
- Concept2 Training Resources — Official training guides and workout plans from Concept2.
- Concept2 RowErg Specifications — Technical specifications and performance monitor details.
- World Rowing — The international governing body for the sport of rowing.
Frequently Asked Questions
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