"A flat run of 9k I was 48 seconds/km faster with a HR of 120"

this week I tried to run like we practised this weekend. A flat run of 9k I was 48 seconds/km faster with a HR of 120 the first time and 42 seconds/km at the second time with a HR of 135. So… This weekend I’ll do a 5K run (cross). I am very curious. But maybe it’s good to do a seminar in the near future again as follow up.

Dre aus Holland, Duathlet/34-Minuten 10km Läufer, 27. November 20015 (5 Tage nach Lauf-Bahn 3.0)