We'll discuss this but I think it's probably too complicated for most users who only need one set of heart rate zones. Also, it's a bit difficult to implement since the zones are linked to diagram graphics, colors and speech output.
Zone 1: Recovery 109 to 139 bpm
Zone 2: Aerobic 140 to 149 bpm
Zone 3: Tempo 150 to 156 bpm
Zone 4: SubThreshold 157 to 163 bpm
Zone 5A: SuperThreshold 164 to 167 bpm
Zone 5B: Aerobic Capacity 168 to 174 bpm
Zone 5C: Anaerobic Capacity 175 to 182 bpm