I have used heart rate measurements periodically in my past training and racing plans, but never really dove all in with it.
This was partially due to wanting to keep things a bit more simple--I felt a bit more "free" running without the technology. I also felt that running without heart rate devices forced me to really tune into my body. I had some relatively brief data that I would use to correlate effort and heart rate, but nothing super detailed like you would see in anyone following a strict Maffetone (MAF) method of endurance training.
I spent the month of June completely away from any structured training. I did plenty of running, relatively speaking, but gave myself some time to just run only when I absolutely wanted to, never waking up in the morning with a specific goal or objective in mind.
As July began and I started nailing down some of the races I want to do this Fall, I also began to re-introduce some structure in the form of a base period of training. The biggest difference with this base phase than any I have done in the past was I decided to build my base almost entirely based on heart rate.
So what does this mean? Basically, I began by adopting a much more strict MAF routine. I wanted my heart rate to dictate my volume and effort in these early stages. If you aren't familiar with MAF training, the basic rule of thumb is you do your endurance training using a formula to come up with your ideal training heart rate for base training:
Dr. Phil Maffetone's 180 Formula (as seen on his website)
For me, this means 180 - 30 + 5 (two plus years uninterupted training) = 155. This makes my ideal range based on the 180 Formula between 145-155.
As I began my July training block, I discoverd quickly that my pace at this range was much faster than I anticipated. My first attempt at discovering my MAF pace had me at aproximately 6:20 per mile with a heart rate of 150 bpm. I noticed that it took a couple weeks of structured training to get comfortable making this routine. But in all honestly, I really enjoyed it. I felt a lot more dialed in and purposeful. Plus, its faster than I generally have done base miles in the past, so the workouts are flying by!
After the first couple weeks I've noticed my HR/pace moving downward a tad. After a few recovery days it was closer to 6:10-15 per mile at a heart rate of 150 bpm. I've also noticed I have been getting a lot more comfortable above 140 bpm. I definitely needed a couple weeks to let my musclular strength catch up with my cardiovascular strength.
My plan going forward is twofold. First, I want to stick with mostly MAF runs as I increase training volume. I will do some light tempo/progression runs occasionally when they feel good, but I don't plan to fluctuate much above 155 bpm. Once I get to where I feel I have platued at lowering my pace at 145-155 bpm I will start implementing some longer tempo/progression style workouts. I hope to also sharpen up with some higher zone 4/5 workouts as race season gets closer. Second, I want to really geek out on how the different variables affect my pace at 145-155 bpm. I have already began dabbling in this and have pinpointed three I want to really focus on: hydration, sleep/recovery, and macro-nutrient ratios. Stay tuned for an update in a future blog post.