It's a truth, universally acknowledged, that if you are a runner, in possession of a regular running schedule, you will find that in the end, the quality of those runs is random.
Most of the time, you will have runs that are of consistent quality, but every now and then, you'll have a run that's just shit, and then, a few days later, you'll have a run that is simply fabulous. There's no explaining this phenomenon. It just is. And, I'm here to inform you that this holds true when you're a pregnant runner as well.
Case in point:
On Tuesday, I had one of those shit runs. Nothing was particularly wrong with it; it just felt slow and hard and awful. But then after the day off yesterday, I hit the path tonight and had one of the best runs that I've had in a long time. I felt fast (well, preggo-fast, which is a kind of fast that's best measured against snails and turtles) and kick ass!
Now, the conditions for the two runs were nearly identical: Same time of day, same weather, and the same eating and hydration patterns. So, no outside factor can be attributed to the difference in quality between the runs -- it's simply a matter of running roulette!