ThisIsNull
commented
7 years ago - custom heart rate zones based on age
- Zone 5 (90-100% of maximum) Zone 4 (80-90% of maximum) Zone 3 (70-80% of maximum) Zone 2 (60-70% of maximum) Zone 1 (50-60% of maximum) see: https://www.polar.com/en/running/calculate-maximum-heart-rate-running https://www.polar.com/en/running/running-heart-rate-zones-basics