New training programme has me doing easy runs at 4:30/km. which is quick! This morning was very cold…so I over gassed it a little. But it felt pretty good.

With a target of 2:40:00 your easy pace is quick. But 4:30 seems a little too quick if that’s supposed to be your Zone2. Race pace + 60” usually. 

Btw impressive that you have 146 bpm at 4:12. What is your max HR?

I agree. 4:30 is a bit too quick. 4:40-4:45 is better I think. But the mileage is low so I am interested in the experiment. A friend of mine did low mileage high intensity training for comrades and ran 30 minutes faster than me…