Train by Numbers - Take 2

Why the use of a heart rate monitor (in this case, the Suunto T6) is a good plan for accurate training:

Heart rate, EPOC, altitude, and splits on 5 x 4 minute level 4 skating intervals. Avg. HR on the intervals: 180, 184, 186, 185, 187... closing in on 90% of max. Train precisely and know that you are getting where you need to go.

-Schulzy