Running race 10:45 [3] 2.5 km (4:18 / km)
ahr:143 max:149
HPP. Intended doing full route but was struggling so stopped to check ECG. Some AF all morning but not severe. Although pace felt comfortable I was tracking MW most of the way and he finished in 21:22 so maybe bit too fast for current level. Got to experiment to experience feelings and see what's realistic though.