I just finished a 12.49km running that lasted about 1hh:2mm:11ss !
Another day helping a couple of friends of mine to do their Marathon Workout.
In particular, 3 blocks of 2000m at 4'30"/km followed by 1000m at 4'10"/km, resting 1' jog between 2000m and 1000m and 2' jog between blocks.
Really a complete Marathon style training.
I have to confess that I did run all of them a little bit faster, specially the last km which I did below 3'50"/km... if I would not do it like that I would have gotten very bored :-)
Essentially it has been a pure aerobical training despite 3' run above the lactate threshold as you can see in the image.
Tomorrow there is a more relaxed but long run which I will joint as well.
Keep on running!