3 mile “tempo” run today. Ran one the previous Wednesday without having read the fine print. Meaning I ran it at a comfortable hard pace for 4 miles straight. Turns out Higdon has you starting out slow, building gradually to something close to race pace for a half mile or so in the middle, then slowing back down for the last mile. Followed that procedure today. I’ve decided to not do any track type speed work till the next 10k. Focus on building a base. That said, I was blown away at the level of improvement I have seen in the past month. Up until Christmas, I was running in a “comfortable groove” of 10:30 ~ 10:45 miles. Since the last week of December I have been holding back to 70% max HR (12 min. miles) for ALL my runs. The 4-mile tempo run last week was at the old “comfortable groove” again, and it clocked at 9:45 miles. A full minute faster! Seemingly without even trying.