Jim Training Blog

Why Aerobic Training?

For a short version of this article, click here.

Why Aerobic / Zone 2 Training?
Reaching our athletic potential and highest performance depends on a training principle that nearly every top coach in all endurance sports subscribe: aerobic exercise, also referred to as  “Zone 2 training”.  

Why aerobic training?  
The body has adapted aerobically over 84,000 generations. While we are often inclined to do more intense and stressful training (mostly due to time constraints and modern living), our bodies have evolved to be most efficient through aerobic training.

You’ll hear aerobic training referred to in a number of ways: Zone 2 or Z2, the 80/20 rule (80% of training is performed at low intensity with only 20% being performed at high intensity), polarization (the approach of “easy is easy and, hard is hard”) and aerobic foundation work.

What is aerobic training and why does it work?  
The heart is the engine that drives the vehicle.  You can have all the fancy bells and whistles you want in that vehicle, but if the engine isn’t strong, those additions are essentially useless. Zone 2 develops the aerobic capacity necessary for peak performance in endurance sports. Technically, anything over a few minutes of exercise is classified as aerobic exercise. As a sprint to Ironman athlete, you are expending energy over a long period of time, such as one to seventeen hours.  The body needs to be able to efficiently endure that level of exertion spread over a period of time.  

Anaerobic training (you’ll see popular reference to HIT or High Intensity Training) may be more exciting, but it is not the most effective way to build the foundation of the engine driving the machine.  The aerobic energy system is the highest priority in developing the overall athlete.  Zone 3 is the “gray zone”--it does very little to develop the aerobic system or the anaerobic system, and yet most athletes naturally fall into this particular category when left to their own devices.  The result is you essentially make very little performance gains in fitness and endurance. Higher zone training will target the anaerobic system and that type of training will be employed secondarily after building your aerobic foundation.  In sum, when looking at the most efficient way to safely and productively develop athletic performance, all research and the scientific evolution of our species have all landed on the same answer: aerobic training.

In addition to the development of your aerobic capacity, there are a number of other critical endurance athlete benefits that come with zone 2 training:

*Increased number and density of mitochondria – your primary energy driver.

*Increased stroke volume, i.e. more blood through your heart and body at the same HR.

*Increased fat burning capability. Maximizing your fat burning capabilities is critical to 2+ hour racing.

*Increased lactate clearance / management.

*Increased blood plasma.

*Ability to Increase overall training volume without beating up your body and mind.  In many cases, we can increase training volume 30 – 50% over your unstructured / gray zone training / Zone 3. You will feel much better, physically and mentally, with the increased training volume in Zone 2.  

Commonly asked questions:

Is this going to suck initially?  
Yes.  If you have not trained Zone 2 HR before, you’re going to most likely hate it. You will sometimes walk hills, you will run and bike slow or slower, and you will long for the days of just doing whatever on your runs and bikes.  You will question your coach and think he is insane.  The suck will continue through the Prep and Base period (but it will get better, promise!).  This is not sexy training.  It is effective training.

When will it not suck?
After the Prep and Base period of the training cycle (lasting from 2 - 4 months, athlete / race dependent), we will begin to add more intensity.   Once you’ve built up your aerobic engine and reached a critical volume of training (another topic), we’ll lift into other zones during the bike and run as we get race-ready during the Build period.  (By nature, your swims in Prep and Base will dip into higher zone training which is where most of our higher intensity i.e., 20% of the 80/20 approach.  You’ll still be getting some intensity in the Prep and Base phase but most of it will be in the water)

When will we reach glory land?

  • When you are running 1 – 2 minutes faster per miles in your Base runs at the same HR than you started the season at.

  • When you are running that much faster during your races at the same level of effort as last year races.

  • When you are passing the people who used to easily beat you.

  • When you hit the finish line with a PR.

  • When you stand on the podium and your friends ask, “What the hell have you been doing?!”

What if I don’t believe you?
It’s always good to be skeptical.  Don’t believe it?  Email 2 – 3 top coaches and athletes in any endurance sport and ask their opinion on Zone 2 / aerobic training.   If they answer anything different than the above, let me know!  I have a sneaking suspicion you will find a common answer between all of them. -Jim

Suggested further readings: The following are various articles that distill this concept and explain it in detail.

Here is the layman’s version of the science of zone 2 training and a great overview:  

  • http://herohealthroom.com/2013/12/04/zone2-training/

A more scientific and detailed explanation of zone 2 training by Stephen Seiler, a world expert on training physiology:  

And:  https://www.frontiersin.org/articles/10.3389/fphys.2015.00295/full

How do endurance runners actually train? Relationship with competition performance.
https://www.ncbi.nlm.nih.gov/pubmed/15741850/

You may have heard of Phil Maffetone, he’s the grandfather of aerobic training and founder of the MAF method:  https://philmaffetone.com/want-speed-slow-down/

Matt Fitzgerald TrainingPeaks article on the 80/20 ratio of low endurance and high endurance training:  

Mark Allen on the maximum fat burning / maximum lipid power benefits of zone 2 training:   

Check out our coaching philosophy. We’d love to hear from you!

White Mt Velo 40-mile Swiftwater Bike Time Trial.

Swiftwater Bike

White Mt Velo 40-mile Swiftwater Bike Time Trial. July 6, 2017. Franconia, NH

White Mt Velo is a road ride group that is supported by Littleton Bike & Fitness. They organize rides from April through September.  Jen Dodge is the current event organizer extraordinaire.  She does the scheduling, organizing the rides, planning appropriate routes, explaining the routes and re-group spots.  You’re always in good hands when Jen runs the show. 

The White Mt Velo group primarily rides out of Littleton, NH but also holds various Thursday night group rides out of other northern NH towns such as Lancaster, Whitefield and Franconia. 

Their Swiftwater 40 mile Time Trial (TT) has been an annual event for over 15 years.  It’s a self-timed ride/race.  Some people ride it as a group and others ride it individually.  Here’s the Strava segment for the course: https://www.strava.com/segments/10040296

Last year’s event was rained out so I was itching to get in on it this year.  It was a beautiful northern NH evening as we met at Mac’s store for pre-ride instructions and information from Jen.  People start when they are ready to launch. I waited a minute or so as to have people to chase. 

The route starts with a 9 mile incline on the Easton Rd / Rt. 116 (part of the White Mountain Half Triathlon uses this road), a right on Rt. 112 losing elevation from miles 9.5 to mile 20 where it intersects Rt 302. It’s a gentle elevation gain for 10 miles through Bath and Lisbon. The crux starts after taking a right on Rt 117 to climb up to Sugar Hill through mile 30 – 35+ ending with a big descent back into Franconia.  

This TT was well-timed with my triathlon season training: For the better part of the Winter, Spring and early Summer, I ran a lot, as in twice as much as I had ever run, as we needed to address fading late in the half marathon part of 70.3s i.e., build run durability, finish the race strong.  As many triathletes can attest, running can sap your high end bike power.  It’s not uncommon to be 10 – 20% off of your ‘normal’ bike power watts with a lot of run miles in the legs during a training phase.  It’s part of the balancing act in triathlon training.  If you want to produce huge watts at your local race or weekly group ride, running can take a backseat for many un-coached athletes.  You have to give a little to get a little (or a lot).  I had completed my A race, Ironman Syracuse 70.3 in mid-June and had backed off the run miles a bit with upcoming shorter races.   In other words, power was being restored to the legs and it was time to push some watts!

As with all races, it’s easy to blow up your entire race in the first half.  I was particularly careful during the first 9 miles, especially between miles 7 – 9 where there are steeper, short pitches.   I didn’t want to burn any matches with big power surges and tried to maintain an even watts range through these hills.  It was tempting to go harder through this part as I had caught my friend, Steve Saffo, and he hooked on and then proceeded to re-pass me on the hills.  Steve is a strong rider (and runner) and I wanted to make the next pass definitive.  As we turned right onto Rt. 112, I put my head down and put in a surge.  Steve was riding a road bike and I was on my TT bike so was able to make just enough of a gap to exploit the rider / bike drag between the two riders and two different types of bikes. 

Recent heavy rain storms had damaged Rt. 112 and it was a rough ride down through the Ammonoosuc River valley, avoiding gravel, potholes and large cracks. In this section, I tried a new fuel source: Untapped Maple.  Due to lack of practice, most of it ended up on my hands and just a bit in my mouth. I had only one package of it. Oops, lesson learned. 

The southwest headwind we had experienced on the first 20 miles turned to a nice push on Rt. 302 as the course rolled north through Bath and Lisbon.  By Lisbon, I was feeling the lack of fueling besides the two bottles of Skratch (one with ice cubes to help internal cooling).  I backed off slightly for the last few miles of 302 knowing that the crux was coming on the Rt. 117 climb into Sugar Hill.   But overall, I was feeling good and it was nice to finally see some real watts (at least for me) on the Garmin. 

Late in races, no matter the distance, is where your fitness level shines (or falters).  As I climbed up Rt. 117, I asked my body to do hard work and it responded.  Those weeks of 1000+ TSS (Training Stress Score) through the Spring and Summer were paying dividends when I needed it.   My power increased through the 5 mile climb and crested Sugar Hill to see the sun’s angled light reflecting off of the Cannon Mountain buildings and bathing Franconia Ridge in warm, orange light.  A true north country evening!

Mile 35+ to mile 38 is a screaming downhill. Not being familiar with the descent and valuing the skin on my body, I sat up for most of it and checked my brakes a few times down through the corners (showing my triathlete side of bike handling skills).  At the bottom, it’s a quick flat sprint back to Mac’s store and done!  Time: 1:44:35 which was 2nd overall on the night. 

To my surprise, I didn’t know there was another guy up the road, ultimately finishing two minutes ahead of me.  Nevertheless, I put out my best effort, was very happy with it and two minutes would have been a tough ask.  Just goes to show, you never know how a race is going to end, keep pushing until the finish line.

Big thanks to White Mtn Velo, Jen and the Littleton Bike & Fitness shop for keeping cycling alive and vibrant in the north country.   - Jim                               (photos credit: Jen Dodge)

Cycling