Training zones are a way to classify and categorize training based on variations of hard and easy. However, the borders between the zones are often arbitrary and not concrete. The optimal stimulus for a training session will vary based on how you feel, and it’s important to dial in your pace range based on your body and mind. While zones are fine for classifying, they are not rigid prescribers of training. The same speed/volume of training can deliver a different stimulus, which gives us a different adaptation. Therefore, it’s important to embrace the nuance of training and not get too caught up in measuring things that may not matter. Instead, focus on being creative and varying your workouts while keeping in mind the goal of slightly embarrassing the body to adapt.

Sometimes, despite your best efforts, you may not feel up to completing your workout as planned. However, it’s okay to make modifications to your workout if you can’t hit your targets without any setbacks. By listening to your body and making adjustments, you can still make progress and maintain momentum. If you push yourself too hard, you may delay your recovery and hinder your progress.

During high-intensity interval sessions, shorter then 1 minute, the primary adaptation is neuromuscular, anaerobic conditioning. it’s important to spend time above your threshold to get the most benefit. If you’re feeling off, skip the next interval to increase the recovery period. If you feel better, keep going. If you’ve skipped an interval and still don’t feel great, end the interval when you can no longer hold the target intensity (power, heart rate, pace). Then, pause the session and double the normal recovery time before starting the next effort. If that helps, keep going and finish the workout. If you can’t maintain the intensity of a given effort, it’s better to end the workout, get some rest, and try again another day.

For intervals between 1-3 minutes, try to maintain the target intensity zone, as long as possible. If your power begins to dip, end the effort and begin your recovery. This will increase the recovery period before the next effort. Start the next interval at 100%. If you’re still struggling, pause the workout and double the recommended recovery time. If you feel better, continue with the workout. If not, it’s better to end the workout and rest.

For sustained tempo or threshold workouts, 5 minutes or longer, the goal is to improve your ability to produce sustained power. Therefore, it’s important to maintain a continuous effort during the duration of the interval. If you can’t maintain the intensity for the entire interval, reduce the intensity by 10%. If you’re still struggling, reduce the intensity another 5% and keep going. Stopping and starting defeats the purpose of threshold work and won’t give you the training adaptation you’re after.