If you train and race in endurance events, you have likely heard the words “zones” and “field assessments” referenced with training. Maybe you use these in your training, maybe you’ve never heard these words tossed around. Regardless of where you sit, this article will provide both a baseline of understanding and help to further your knowledge of how to train smart, understand where zones come from and how they play a part in the bigger picture of maximizing your potential. So, let’s talk about the importance of field assessments and zones and how they tie together.
To understand your current fitness, you need to determine a baseline. While this can be done in human performance labs and other facilities through VO2 max and other testing, for most, this is not a realistic option. Alternatively, one way to estimate your current fitness level is through field testing. Field testing is exactly what the words imply, tests run “in the field” of your sport of choice. Field tests not only determine a baseline of your current fitness, but allow for progress measurement, zone development and potential to be maximized. Field tests should be completed for every aspect of multi-sport you participate in. For a triathlete, these assessments would be completed in the swim, bike and run. They should be penciled into your training at the start of your training and every 6-8 weeks thereafter. If you’ve never completed one before and you’ve been training for a while, now is the time to start.
The goal of the field assessment is to push as hard as you can, maintaining as even of a pace as you can for the duration of the assessment. Ideally, the assessment is completed on fresh legs in the same modality (road vs treadmill, road vs trainer and swimming in the same distance pool), at the same time of day and following the same pre-workout nutrition with each occurrence. For the bike, this field test typically consists of a 20 minute all-out effort. The run, typically a 5k. For the swim, I typically like to use a 1000-yard test. These field tests offer reliable data to measure where your fitness initially started, to track improvements over time and to identify specific pace, power and/or heart rate zones to be used with training. With that said, data recording is imperative; track heart rate, pace, power and mileage.
This brings us to zones. Zones are a way to apply and gauge intensity within your training and each zone is a percentage of your threshold from the field assessment. Depending on the modality and what tools you have at your disposal, zones will either be set in power, pace, heart rate or rating of perceived exertion (RPE).
Completing these field assessments is crucial to maximize gains. Through training, we adapt and become faster, stronger and build endurance. When training in zones, you train based on a specific percentage of your maximal effort, so it's important to consistently measure and gauge changes or improvements in this number. As you improve and increase speed or power, threshold changes. If we don't re-measure on a consistent basis, zones may be wrong and training may be at too low of an intensity. If training is at too low of an intensity, improvements are minimized. While improvements are not always seen every 6-8 weeks (progress sometimes isn't seen for several months at a time) it's still important to re-assess, gauge and document the data to know you are on the right track.
This is one component in training smart and why it's important to stay within the zones for each segment of your workouts. Research indicates the best training for endurance athletes to improve both speed and endurance while preventing overtraining and reducing the risk of injury is to apply the 80/20 rule. The 80/20 rule is where 20 percent of your training is done at a high intensity and 80 percent at a low intensity. When this principle is applied in your training, either through a good coach or done yourself, be sure to follow the workout as designed. Focus on each segment. Push hard through the thresholds and intervals, dial it back on the easy intervals, recoveries and long rides, runs and swims.
Get in the zone, sit in that discomfort and you will soon be stepping into new zones, faster speeds, higher power and greater performances.