Running (xc/terrain) 50:25 [2] 5.0 km (10:05 / km)
ahr:145 max:157
Exploring again, looking for some good routes through the terrain in order to design a long, hilly run. Some good ideas but also some less ideal, crappy bits.
I've worked out how my Garmin estimates the hr zones, based on 220-age max heart rate then 10% blocks from there. I think I may be able to tweek these a little more personal without requiring a professional metabolic assessment :)
In any case I'll carry on with my own estimations with AP intensity i.e. it can't be an intensity 5 session if I can maintain the level of effort for more than a few mins.