Friday, January 29, 2016

Rebuilding my Aerobic Engine

Now that I'm about two months in to my MAF experiment, I thought I would share a bit about my experience so far and some of the reasons why someone would train with heart rate (but mostly specifically, with an aerobic threshold heart rate).  The biggest lessons that I have learned include being able to set your ego at the door, embrace the journey, and be patient!  This method has represented a very significant departure from my previous training, and it has certainly been trying at times, but I've made a vow to myself to be open to the process!

The Method:

How did we set my heart rate? 

The 180 formula, which Phil Maffetone developed over decades of working with athletes of all ages, abilities, and fitness levels, goes like this to determine your MAF (Max Aerobic Function) heart rate:

Start with 180.  Subtract your age. Subtract 5 if you have health issues (diabetes, heart disease, recent and frequent colds/flus, recent antibiotics use, high levels of stress, etc.).  Or add 5 if you are never sick, have little stress and are very fit.

For me this resulted in a starting MAF HR of 146 BPM.  I am 29, but in the fall I was sick for about a month after being on antibiotics.

When I started with my coach, Jon, he had me do a test workout.  He set my heart rate and told me to spend 15 minutes warming up (bringing heart rate gradually to MAF HR), then stay there for about 30 minutes, then spend 15 minutes cooling down.  We recorded my average pace during the 30 minutes at MAF. This is the primary test.

So I did my first test set at 146 HR and my average pace was 10:40/mile.  At that point, Jon determined that my aerobic system was sh*t.

Since that first test, I've tried to keep every single workout - swim, bike, run - below my MAF heart rate.  As my health and fitness levels have improved, Jon has slowly added beats to my HR, so now, at 2 months in, I'm working at a 153 HR.

According to Phil Maffetone, it is very important to stay below the MAF HR threshold during the aerobic system building phase.  Once over that threshold, we begin to use our anaerobic system and in the early stages that is detrimental to the development of our aerobic system. It can be hard and very frustrating at times to stay below the threshold.  Often I spend workouts stressed out about raising my HR and then see my HR spike because I am stressed! But I'm trying to stay patient.  I was very lucky to have started this phase when I did, since typically it's recommended to spend 3-6 months building the aerobic system in this way. As long as you see improvements in your pace during the test, you continue with the below threshold training.  Once those improvements stop, you can add in some speed work!

Now, staying below MAF HR isn't the only element.  The other key elements are nutrition and recovery.  The nutrition aspect involves finding the optimal level of carbs for you in a fairly low-carb, high-fat diet (I did the two-week test, though I'll do it again since I went straight into Christmas after mine).  I have a lot more to learn about the nutrition aspect, but the gist is that we want to maximize our ability to burn fat stores.  Getting adequate rest and recovery, as well as limiting stress, are the other keys.

Why train like this?

As competitive, always striving for stronger, faster, fitter athletes, it can be very tempting to go hard all the time.  We have limited amounts of time to train, so we might as well give'r every workout, right?! We have to train fast to race fast, right?!  Well, maybe not always. Maybe with a lot of patience, we can improve our aerobic system to the point where we are getting faster without putting too much stress on our bodies, allowing us to recover quickly between workouts and stay injury-free.  As I began to read about Phil's methodology, it really started to sound like something I wanted, particularly after spending most of last season dealing with a stress-fracture.  I'm open to trying something new in order to get faster and healthier. This phase is about improving my aerobic capacity, which will be very beneficial going into season and my first half ironman. So I'm slowing down to get faster!

So, how's it going? 

Well, it's hard to say.  I started my MAF training before the snow arrived, but since then we've had really poor conditions - snow, ice, etc. - and I refuse to run on the treadmill.  From a pace perspective, I think my MAF pace is improving, though I haven't had great conditions to test it. Likely closer to 10:00/mile now than 10:40/mile.  Ideally, I'd get my MAF pace down to about 8:00/mile. I just did my first power test on the bike with my MAF HR last weekend, so I'll have to wait a bit to see if there are improvements there.  And as we know, I haven't been in the pool at all! I'll keep you posted.


  1. Slow down to get faster is something I'm trying hard to do! I hear Tawnee on Endurance Planet talk lots about MAF and I've wondered what that would really look like. Cool to read how it's going for you! Nice work!

  2. Everyone says slow is the new fast!!! I've heard it works so good luck!! :)