Monday, August 19, 2013

Zone 2 Training Works...But Not Today

Over the last two years or so, the topic of Zone 2 ("Z2") training has been mentioned, discussed and written about all over the web and in almost every endurance sport related podcast.  I (John) have been training with Z2 for the better part of 2013 with tremendous results.  I thought it was worth sharing my experience(s) and how it could help you in your training.

***** Disclaimer: I am not a trained health or fitness professional.  The following is simply my experience with a particular training method. *****

A good place to start is with a definition of Z2 training.  Zone 2 refers to your aerobic heart rate range, and specifically training within that zone.  Typically, endurance athletes use five (5) heart rate zones to identify the level of effort and exertion while training or racing.  You can use a good heart rate zone calculator to find out the upper and lower heart rate limits for each zone.  It is also advisable to recalculate your zones periodically.  Monitor your resting heart rate and then comb through your data for your max effort heart rate (typically from a race).  I would say every 4-6 months would be sufficient.

In order to effectively utilize Z2 training, you must first check your ego at the door and then adjust your perception of a training session.  I used to plan my training by targeting speeds and distances.  "I am going to run 6 miles at an 8 minute/mile pace."  The following week, I would up the mileage a little, and hope to maintain the same pace.  If the pace dropped, I must be having a bad day.  If the pace increased, I must be getting stronger; until I increase the mileage again.

This whole cycle brought me right to the point of mediocrity, also known as a plateau.  I just couldn't go any faster or farther.  The idea of ever running a full marathon was painfully out of reach.  Enter Z2 training.

Check Your Ego At The Door

To get the most out of this system, I realized I needed to be humble.  In the beginning, I averaged 15 minutes/mile on my runs and 15 miles/hour on the bike, much slower than I was "comfortable" with.  Soccer Moms with jogging strollers and teenagers on BMX bikes passed me by on the slightest of inclines.  I had to stop running at that breakneck pace of 15 min/mile to walk for 100 yards.  And when my neighbor was standing in their yard while I shuffled on by, I wanted to bury my head in shame.  Handling the humility of Z2 training was probably the most difficult aspect.  I wanted to bag the whole concept, but thankfully I didn't.

Change Your Perception Of A Training Session

Once I had my ego in check, I had to look at training sessions a little differently.  I was now training by heart rate and time.  Notice, I didn't mention distance or speed.  That's the difference.  I scheduled sessions such as "run for an hour in zone 2" with no regard for distance and/or speed.  I simply had to move my body while keeping my heart rate in the right zone for a specified period of time.

Typically, I will run "out" for 30 minutes and "back" for 30 minutes.  If my heart rate starts to creep toward zone 3, I slow it down a bit to stay in zone 2.  Since I have heart rate alerts on my Garmin device, I set the alert a few beats below the top of zone 2.  This informed me when I was getting close, giving me some time to get my heart rate down before going over the limit.  I still employ this practice today.

My goal was always to get 100% of my training time in zone 2.  Obviously, I spent some in zone 1 as I warmed up and possibly touched zone 3 if I overdid it a little.  Not too much of an issue, because this got better and easier.

Stay Indoors At First

When I started this type of training, I threw away my hatred of the treadmill or bike trainer.  Since it is a much more controlled and static environment, it allowed me to truly hit the target for workouts and trained my body to work more efficiently across larger blocks of time.  A good time of year to really commit to Z2 training is the late fall, going into winter.  Most of my training would be indoors anyway, so I got to make the most of it.

Be Patient

This was not a quick-fix, overnight plan that made me a better endurance athlete in a few weeks.  It took time.  It took a lot of time.  I started to see small benefits in about 3 months.  At about 5 months, I started to see some huge gains.

For example, here is a breakdown of a treadmill run on March 20th:

  • Total Time: 60:00 minutes
  • Zone 1: 03:00 minutes
  • Zone 2: 57:00 minutes
  • Average Pace: 14:22 min/mile
  • Average HR: 124 BPM

A few months later on June 7th (treadmill):
  • Total Time: 90:00 minutes
  • Zone 1: 11:00 minutes
  • Zone 2: 1:19:00 minutes
  • Average Pace: 13:39 min/mile
  • Average HR: 123 BPM

A few weeks ago on August 1st (outside):
  • Total Time: 50:00 minutes
  • Zone 1: 03:00 minutes
  • Zone 2: 47:00 minutes
  • Average Pace: 09:57 min/mile
  • Average HR: 125 BPM

It took 5 months, but I broke a 10 minute mile all in zones 1 and 2.  At this point, I could basically run all day in zone 2, and do it at around a 10 min/mile pace.  That is a huge improvement in my aerobic engine.  I am hoping to be able to run a 3:30:00 marathon by this time next year, all in zone 2.  The progress that I have made thus far, gives me confidence that I can.

Eat More Fat

Another aspect of training that coincides with Z2 training is diet.  When I train in Z2, I am primarily burning fat.  I sparingly trickle small amounts of natural sugar sources when I am training or racing in the higher zones.  By primarily training in Z2 and consuming a lot more fat from healthy sources, my body has become much more metabolically efficient.

I substantially increased my fat intake earlier this year and routinely do 3 and 4 hour training sessions in a fasted state.  I will consume about 150 calories throughout the training session and hydrate with Nuun.  I no longer have a need (or desire) for gels or sugary sports drinks.  Fat as fuel is the way to go.  No bonks, no sugar crashes.

Mix It Up

By no means is this the only training I do.  It is the vast majority of the hours, but I still need to get my body ready to go fast.  I throw in intervals, speed work, hill repeats and strength workouts, but spend most of my time in Z2.  I also found that when I do let the hammer down, I have more horsepower at my disposal.  But I am very careful not to overdo it.  I use Training Effect on my Garmin to limit myself and allow for ample recovery.  You can read more about Training Effect ("TE") here.

This is my HR Zone breakdown for the last 4 months.  Zones 1 and 2
make up over 66% of my total training time.
Avoid Injuries

An added benefit of training the Z2 way is I tend to avoid injuries.  Long gone are the days of pounding my knees and legs into the ground with hours of tempo and threshold efforts.  Training at lower intensities allowed me to focus on form much more often.  I went from a heel-striker to a mid-foot stride in a very short period of time.

I have also incorporated the use of a weight vest during my Z2 runs.  This is a very dangerous practice if not done correctly, so I would not recommend it to newbies or anyone that has not done a ton of research.  I will compose a post on the use of a weight vest in the near future.

I have not had a single injury or even a "niggle" this year, and I can attribute that to extensive Z2 training.

Z2 Versus Maffetone

To the best of my knowledge, and through extensive research, Z2 training and Phil Maffetone's method ("MAF") are essentially the same thing.  They only differ in the zone calculation.  The MAF zone will typically be slightly higher than a Z2.  However, they are both rooted in the same concept of training in your aerobic zone, below the point where your body flips from burning mostly fat to burning mostly carbohydrates.

For most people, Z2 and MAF would be interchangeable with regards to building a solid aerobic base.  I have chosen the Z2 method, but I am sure MAF would have yielded similar results.

Starting Out

When I first started out training with Z2, I had a tremendous difficulty keeping my heart rate in the correct zone.  One little trick that I used was to forget the numbers for a while and train by feel.  I did this by using the way I speak as a gauge.  Before I started a training session (at rest), I would speak my full home address, "123 Main Street, MyTown, New York" in a normal, conversational speed and tone.  I could speak this aloud on one breath when I was at rest.

Once I started the training session, I would periodically recite my address in the same fashion as before.  When I got to a point where I either needed to take a breath mid-sentence, or had to speed it up to get it all out on one breath, I knew I was out of that aerobic zone.  That is when I backed it down a bit to where I could recite it correctly.

Although I would record my heart rate data, it was not the driver of these sessions.  After a few weeks, I could see that data showed improvement.  30% in zone 2, then 35%, then 40% and so on until I was ready to start training BY my heart rate, rather than WITH my heart rate.

What Is The Goal?

Although Z2 training encompasses a large portion of my training volume, I also do a fair amount of hard interval, tempo, threshold and "to failure" training.  With all of these variations, I am able to concurrently build endurance, speed and strength.  So the question is, "what is the goal of Z2 training?"

The main goal of Z2 training is to build a solid aerobic base for endurance activities and events.  The longer the event, the more beneficial Z2 training becomes.  For example, Z2 training has almost no impact on my sprint distance races, a moderate effect on my Olympic distance, a great impact on my 70.3 and will play a HUGE role in my full Ironman next year.

My training goal is to get my Z2 paces to be my expected race paces.  I figure if I can do 75% of each leg in Z2 while achieving my desired race pace, I can drop the hammer for the last 25% and have the horsepower available that others will not.  Effective Z2 training should prevent me from blowing up prior to the finish line.

I have established time goals for Ironman Lake Placid next year.  One of them is to run the marathon segment in 4 hours or less.  That equates to running at a 9:10 pace for 26 miles.  As of this week, I can run at a 9:58 pace for 2+ hours.  With a full year ahead of me, I am very optimistic about meeting or exceeding this goal.  Only time will tell, and I have the time and patience to do it.


For me, a competitive triathlete, Z2 training has been the difference between a "middle-of-the-packer" and the podium.  It is something that anyone can employ with a little discipline and patience.  I have also come to understand that this method is a long-term way of perpetually gaining fitness without the risk of a huge burn out at the end of each season.  It is the perfect method if you are just starting out, have hit a plateau or just want to go longer.

Please follow us, as I will be updating my progress throughout the year.

Connect with me on Twitter.


  1. I really need to try heart rate training one day. I have a hard time with the discipline to make myself go as slow as I'd need to. But I wonder if this type of training works better if you have a certain number of hours to devote to it? Like, if I know I only have X numbers of hours in a week to train, would I get better results doing the typical one speed day, one tempo, one long and slow? In other words is there a critical number of hours of this before it "works"?

    I'd be curious also to know how much you would have improved if you'd done traditional training and then compared the two. Not to get too nerdy about it but there's really no Control in this experiment, you may have improved as much or more with different training.

    Great recap of the training though, you explained it really well. I'm amazed you can stand to run 14 minute miles on the treadmill! You must have a really good book.

  2. J-

    I actually have a sort of control for comparison. I hit a plateau last year using "traditional" training methods. Couldn't go any faster, couldn't go any farther than the year before. Although not an ideal control, I think it has some validity.

    I would say that working on a percentage basis might work well. If you have 10 hours a week to train, 7 hours are in Zones 1 and 2, 2 hours in Zone 3 and maybe an hour in Zone 4. An hour per week in Zone 4 will do all the damage you need to gain speed and strength.

    Thankfully, I am not running at 14 min/miles any more, but podcasts, and a whole bunch of them, got me through these session.

    Thanks for reading, we appreciate the support.


    1. Thanks for the reply :) I am so limited in time that I can train that I always assumed the best bang for my buck was doing the hardest workouts I could for the time given, but that may be impeding me rather than helping me. I think every individual should try all different ways because I think we are all different in how we respond to things training-wise...I have some friends who race better if they run the day before, others (like me) who do better on a taper...all so varied.

  3. I have to admit that I have worked on tryin to do HR training for the better part of 3 years, getting frustrated with the process an quitting UNTIL I started throwing in speed work. I somehow missed that memo.

    Anyway, I do better at staying with it on the run than the bike. Which probably explains why my bike has stayed the same and my run has improved. I plan on heading into next season building my aerobic base ad sticking the HR training all around this time.

    Nice post BTW!

  4. Mandy-

    Thank you. You are not normal! Most people can more easily control their HR on the bike and struggle with the run. In fact, Brett made me adjust my bike zones 5 BMP lower than the run. Try riding outside, in wind, on hills and keep your HR lower than 128, while maintaining a respectable speed! Not very easy.

    Congrats on your IMLP finish, and thanks for the support.


  5. John,

    This helped a lot. I am going to be buying a Garmin 910XT for training for my ironMan next year (Our ironMan). My biggest questions are:

    1. I show my resting heart rate at about 58. It seems low, but then again, I've heard it to be much lower for athletes. Does this make sense? I guess I need to check it regularly to get a solid basis, but is this number even close to reality?

    2. If I start Z2 training this fall, do you think it is too late for our ironMan next year? Will it enable me to be efficient by then? Perhaps we can discuss a training regimen (like # hours / week) that would make sense for me to have an efficient training prior?

    3. Nutrition - do you have any articles specific to your nutrition philosophy of burning fat and the types of "good fats" you are referring too? I do not like the GU gel philosophy and would really like to burn fat more efficiently.

    Great read, and buddy I really look forward to learning a lot from you. You're awesome and I'm looking forward to my new found friendship with the Newman's!


  6. John-

    Thanks for the support, we really appreciate it. Here are short answers, I have a few more "technical" posts in the works that could answer them more completely.

    1) Resting HR of 60 is "normal". The more fit you are, the lower it will be. I am right around 45-47 on most days. I track it every morning as soon as I turn off the alarm. If you are at 58 when you are sitting on the couch during the day, I would bet that your real resting HR is lower. Check it while you are still in bed. I am also testing the effectiveness of Heart Rate Variability ("HRV"). When I have more data, I will post about that one too.

    2) You have more than enough time to get a benefit for IMLP. You can see a huge improvement in 12-16 weeks. We have about 48 weeks. Plenty of time.

    3) Nutrition is so varied and complex, I have to break it down to multiple posts (in the works). There is a really simple solution to start out on the path to being more metabolically efficient and fat adaptive. Ready, here it is....No Sugar, No Grains (#NSNG)! That's it. Cut out those 2 things and eat EVERYTHING else. Check out Vinnie Tortorich's book "Fitness Confidential".

    See you on Saturday.


  7. Hi All,first of all i wanna say thanks a lot to the writer . I was almost about to give up on zone 2 . and then i read this article and up for giving it 1 more than. My coach is also fan of zone 2 . So i have started doing it. I am doing all my run in zone 2 . all outside . Currently i am running under 13 pace in zone 2. My best pace is 11.06 min /mile in zone 2.I felt like pace is not linear , i mean one week i did under 12 pace (all my runs) ..and next week it goes almost 13. I think its weather or my condition how fatigue I am. its been 6 weeks as of now. Lets give it another month. i will keep you posted sir. let me know if you're still making progress in Zone 2.

  8. Thanks for this! Just started Z2 training last week and it's painfully slow. But reading about your 14-15 min/miles starting out made me feel a bit better about having to walk/run and coming home with a 13:42 min/mile average. Sounds like patience and consistency is the key. Duh, of course it is. :)