Training Zones Explained

The Importance of Zone 1 and Zone 2 Training

Zone 1 and Zone 2 training help you build endurance, durability and strength. In addition, these easy training sessions help build capillary pathways that transport oxygen to your muscles and carry waste (lactate) away from your muscles. The more capillary pathways that you can build, the more efficient you will be. Efficiency is equal to free speed.

If at first you can't keep your HR under Zone 2, then you need to slow down. If that means you run for three minutes and walk for two minutes to keep your HR down then, by all means, do it. For a fit athlete getting back into training, I recommend training without a heart rate monitor for two weeks. Put it back on once you have a sense of fitness coming back. You may feel that training in Zone 2 and under is a step back, but you will see the progress over time and you will be thankful you were patient during this important phase.

Adaptation for everyone will be different. Some people will see changes right away, and for others it may take months. Just this year I had an athlete drop about 40 seconds a mile on his long runs after two months of Zone 2 training, and he's been racing and training for over 20 years. So, at any level, improvement is possible. You just need to have faith in the philosophy and, above all else, be patient.

RPE Zone HR Description
0 Z1 Resting HR
 Complete rest.
1 Z1 Very Easy Light walking.
2 Z1 Very Easy Light walking.
3 Z1 Very Easy Walking.
4 Z1 Still Easy Maybe starting to sweat.
5 Z2 Starting to Work You can feel your HR rise.
6 Z2 Working but Sustainable Can talk in full sentences.
7 Z3 Strong Effort Breathing labored, but can still maintain pace for some minutes without slowing.
8 Z4 Olympic-Distance Race Pace This is your lactate threshold / your best effort for one hour.
9 Z5 10K Effort Very hard.
10 Z5 5K Effort Cannot hold effort for more than a minute or two. (almost max effort).

Note: All D3 training plans were created with these heart rate zones in mind.

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Mike Ricci is a Level III USA Triathlon Certified Coach with more than 20 years of coaching experience.  In 2000 Mike founded D3 and has slowly added top-notch coaches each year to handle the demand for high quality triathlon coaching. In addition to coaching the 2010 and 2011 National Collegiate Champions, Mike is the University of Colorado Triathlon Team coach. He can be reached for personal coaching at mike@d3multisport.com.

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