What Is The 80-20 Intensity Balance Rule & Can It Improve Your Enduran

I’ve been around the sport of CrossFit for a little over 10 years now. I can remember back to a time when anything but high-intensity, train-to-the-point of-near-death type workouts were the end all be all of training. Easy workouts like long Zone 2 runs were mocked as anti-fitness. I even remember a few posts that placed jacked elite CrossFit athletes next to some of the best endurance runners in the world and asked something like, “Who’s fitter?” Their contention was that the runners lacked muscle and an overall healthy lifestyle.

Well, it's 10 years later and a lot has changed. Today, you’d be hard-pressed to find an elite CrossFit athlete that doesn't spend at least a few hours a week on long easy bike, run, row, or swim sessions.

Of course, it was only a matter of time before CrossFit caught on to what most of the endurance world already knew. Most elite endurance athletes spend anywhere between 60-80% of their total conditioning time in Zone 2. The more volume they have in their training, the bigger the Zone 2 percentage. This has been proven through data from different elite coaches in different sports and in the scientific literature.

Benefits of Zone 2 Training

Before we move on to how to incorporate Zone 2 into your training, let’s quickly highlight some of the benefits.

• For starters, there are many psychological benefits including: Building confidence in your ability to sustain long efforts and the body-awareness and athlete IQ to properly pace a workout. In addition, for many athletes, the long run requires a great deal of mental toughness - an asset in any athletic endeavor!

• Mitochondria biogenesis: In short, one of the basic roles of the mitochondria is to convert the food we eat into energy. The more mitochondria we have, the more energy we can produce. Zone 2 workouts increase the total number and size of mitochondria in our body.

• Improved fat oxidation. Zone 2 training teaches your body to use a higher percentage of fat for fuel, thereby improving your aerobic threshold, or your body's ability to train longer and harder without going into an anaerobic state - where carbohydrates are the preferred fuel source.

• Improved lactate clearance. Zone 2 training stimulates type 1 muscle fibers which play a key role in lactate clearance. Clearing lactate is key to athletic performance because it delays the onset of fatigue while increasing the energy available to your working muscles.

How to Add Zone 2 to Your Training

For most CrossFit athletes, I recommend, at minimum, a 60-40 intensity balance. That means 60% of your total non-strength training should be done at Zone 2. The remaining 40% will be done at higher intensities. The higher your total training volume, the higher the Zone 2 percentage should be, up to the aforementioned 80-20 intensity balance.

Example Training Week With a 60-40 Intensity Balance

Keep in mind, we’re not including any strength or skill work. This is just conditioning work.

Monday
10-Minute AMRAP
30-Minute Zone 2 Bike

Tuesday
20-Minute Chipper

Wednesday
15-Minute 3-Round Workout
40-Minute Zone 2 Row

Thursday
Full Rest Day

Friday
Strength & Skill Work Only, No High-Intensity WOD
45-Minute Zone 2 Row

Saturday
24-Minute Partner Workout

Total High-Intensity Training Time: 69 Minutes (37%)
Total Zone 2 Training Time: 115 Minutes (63%)

Conclusion

If you want to get better, you have to spend a large percentage of your training time at low intensities. As seen in the example provided, this can be done by adding 2-3 extra Zone 2 sessions a week.