In this episode of Breaking 40 I'm talking about one of my biggest challenges with Low Heart Rate Training so far: How it doesn't have the same soothing/therapeutic effect as running all out have. I'm also sharing a couple of big wins and a bit of disappointment as we go through week 3, 4 and 5 of this low heart rate experiment as I'm testing the MAF-method in my pursuit of running a sub 40 minute 10k one day.