When training for endurance, training sessions must have a specific purpose. Simply going out and swimming, biking, or running with no planned duration or intensity might bring some improvements at first, but it will quickly lead to a plateau and possibly even injury. To really improve your endurance performance, training sessions must focus on different intensities and durations specific to you and your race distance.
How are intensities and durations measured? Duration is simply measured in time with a stopwatch or distance with a GPS watch or other measuring method. Measuring intensity on the other hand isn’t that simple, which is why over time endurance coaches have created certain “zones” to gauge intensity.
These training zones are defined differently depending on the coach. Some coaches label zones as easy, moderate, and hard. While others use terms like aerobic sessions or anaerobic sessions. I personally believe the easiest and most effective training zone model is the 5 training zone model which has been made popular by arguably the greatest triathlon coach ever, Joe Friel. Below, each zone is explained in detail along with its specific purpose.
Endurance Training Zones
Zone 1 is also known as the “recovery” zone. In zone 1 heart rate, pace, power (bike only), and effort is very low. The purpose of this zone is to speed up recovery by moving between workouts. For example; after a day of hill repeats an easy 30 minute bike ride in zone 1 can recover athletes faster than simply doing nothing. Zone 1 training sessions should be completed year round in recovery workouts and in the “prep” phase of an endurance athlete’s season.
Zone 2 is a very common zone among ultra endurance athletes (ironman triathletes, marathon runners, long distance cyclists) because long endurance sessions are completed in this zone. Zone 2 is also known as a “conversational” effort because you’re going easy enough that you can hold a conversation with a training partner. Zone 2 workouts include steady long efforts such as a 3-hour bike ride or 1-hour long run. Zone 2 training sessions are primarily done in the “base” phase of short distance endurance athlete’s season, should be used year round for long distance endurance athletes.
Zone 3 is interesting as it’s just below lactate threshold making it not “hard” but not “easy”. Zone 3 is a zone where the effort is difficult but maintainable. You should be able to say short sentences while breathing but you shouldn’t be able to hold a conversation like Zone 2.
Zone 3 training sessions are primarily done later in the “base” phase of training and early in the “build” phase. Short distance endurance athlete’s season should being Zone 3 workouts sooner than long distance endurance athletes.
Zone 4 is also know as the threshold zone becuase during this training zone you should be at or slightly above your lactate threshold pace. Zone 4 efforts are hard; you should only be able to get out a few words between breaths while training in Zone 4. Zone 4 training sessions are commonly seen in the “build” phase of an endurance athlete’s season.
Zone 5 is a sprint effort, heart rate is above lactate threshold and you should barely be able to get out one word while in this zone. Track sprints, short hill repeats, and other short fast efforts are commonly done in Zone 5. Zone 5 training sessions are seen in the “build” and “peak” phase of an endurance athlete’s season.
Now that you understand training zones, stay tuned for next week’s article on how to establish your training zones!