There are a variety of school of thought on how to determine the difficulty of a workout or exercise program. Some of the factors that include volume, frequency, intensity, or heart rate. One style of measuring training difficulty is using 1-5 Zone Based Training.
Zone 1: Easy Movement
Training in Zone 1 is very light movement. It is physical activity but you will not be tired when you finish. Going for a walk or warming up is often in Zone 1 range for most people. It should be incredibly easy to hold a conversation while you are in this zone and you will not have muscle fatigue.
Zone 2: Light Movement
This training level is an important training zone (more on that later). It helps build cardiovascular base and can be used as recovery from more intense training levels. At this level you should still be able to hold a conversation without taking long breaks to breath. It is intense enough that someone on the phone with you would be able to tell from your breathing that you are exercising. At this level, you should still not be experience muscle fatigue and could sustain the work rate for a long period of time. Walking uphill or controlled pace biking is a common method for getting into Zone 2. Unless you are an elite runner, running will typically put the person into zone 3 or higher.
Zone 3: Moderate
The intensity for Zone 3 training when you are in the middle of your aerobic base. Exercising at that this level could be done for extended periods of time and will start to develop light muscle fatigue. A conversation will be possible but would be sporadic in this training zone and would require breaks to allow for breathing. This zone is common in long distance running.
Zone 4: Intense
As you continue increasing the intensity, you will transition from aerobic to anaerobic training. At this level you will not be able to have a conversation. You will develop muscle fatigue. The work rate in Zone 4 is not sustainable for more an a few minutes. This is the level that is often used in interval training.
Zone 5: Max Effort
The highest intensity range is Zone 5. This is all out effort and completely anaerobic training. There will be a high level of muscle fatigue and the work rate can only be sustained for seconds to a minute or two. Sprinting or short bursts on an air dyne bike are common examples of exercise which result in Zone 5 training.
Your Training Zone
Which training zone should you be in? The answer is going to be the same one that a lawyer often gives… “It depends.” Your training goals will be the biggest factor in how much time you spend in each level. Unless you are training for peak performance in a specific event, it is beneficial for healthy individuals to spend some time in all 5 training zones.
Most people spend almost all of their time in Zone 3 and Zone 4 and typically spend very little time in Zones 1, 2, or 5. As a result, it is common for individuals to plateau or collect injuries. Make sure you include physical activity in all five training zones to become fitter, healthier, and happier.