Unlock your potential: Understand and utilize training intensity zones

How do I measure training intensity?

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Training intensity can be measured in several ways:

The best method to measure training intensity will depend on the activity you participate in and your available equipment. Let us continue by exploring each measurement and its pros and cons.

Perceived effort

The perceived effort, also known as the Rate of Perceived Exertion (RPE), is a self-assessed and subjective measure of how hard an individual feels working during physical activity. It is typically measured on a scale of 1 to 10, with 1 being the least and 10 being the maximum effort.

The RPE scale is a simple and accessible tool that can be used to monitor training intensity and progress. Unlike other measures of training intensity, such as heart rate or power output, the perceived effort can be easily assessed without any special equipment. And it can be used in various settings, including at home, in the gym, or outdoors.

Pros

The main advantage of RPE is that it is an individualized measure, considering your current fitness level, how you feel that day, and how you respond to different types of exercise.

RPE is a practical measurement when training in different environments, as a heart rate monitor may not work correctly at high altitudes or in extreme temperatures.

Another benefit is that it does not depend on external gadgets, making it very convenient for a beginner without all the gear.

Cons

One potential disadvantage of the perceived effort is that your psychological state and external factors like fatigue, hydration, stress, and sleep can influence it. That is why it is important not to rely solely on RPE as the only measure of training intensity. Instead, use it with other metrics such as heart rate, power output, or pace.

Additionally, RPE is a self-reported measure; thus, the accuracy of the results may be affected by your ability to gauge your own exertion level. In some cases, athletes may overestimate or underestimate their own exertion, which can impact the accuracy of the data.

Pace

Without getting too technical, the pace is another way to describe the speed in training and racing.

For example, a runner may have a pace of 8 minutes per mile, meaning it takes 8 minutes to run one mile. Or you swim in 2:15 minutes per 100 meters.

Pace zones are typically calculated as a percentage of your personal best performance for a given distance or based on your threshold pace. More on this later.

Pros

The foremost benefit of using pace zones is that they can provide a clear, specific, and measurable target for training.

Additionally, pace zones are a useful measure of intensity in sports where heart rate monitoring may be unreliable, such as swimming or running in hot weather.

The pace is also helpful in tracking progress over time by comparing current pacing with previous training sessions or races.

Cons

One weakness of pace is that it can be affected by external factors such as terrain, weather, and altitude. For example, suppose you are trail running. Then it is challenging to keep a certain pace due to the topography, making heart rate a better way to keep track of your effort.

Another disadvantage is that it may be affected by equipment, for example, when running on a treadmill. In that case, the pace may be affected by the calibration of the treadmill, making it less reliable as a measure.

Power

The power measurement, as measured by a power meter, is particularly well-established in cycling. It provides a real-time measure of the work being done by you, allowing for precise and accurate measurement of training intensity.

When using a power meter to measure training intensity, you can set specific power-based training zones, much like heart rate or pace zones. These power zones are typically based on a percentage of your functional threshold power (FTP).

Pros

Power meters usually provide additional information such as cadence, pedal stroke, and power distribution which can be used to analyze and improve technique.

Again, the power measurement is most applicable in cycling and other power-based sports, as it is based on the amount of energy (work) you produce.

Cons

Power meters are less applicable in other sports, such as running or swimming, as there is no direct measure of power output. However, power meters are now becoming available for running. Still, as of writing this article, they are less common and may not be as accurate as in cycling.

Heart rate

Heart rate is the most common tool to measure training intensity in endurance sports.

The heart rate measurement is based on the principle that as exercise intensity increases, so does heart rate. Therefore, by monitoring heart rate during your training, you ensure you are training at the appropriate intensity to meet specific goals.

Pros

Heart rate is relatively easy to measure and can be done with a heart rate monitor or a simple manual pulse check.

Today, all smartwatches can show this variable, which makes it very accessible.

Additionally, it provides a measure of overall cardiovascular fitness and recovery status. In this context, it can give you an insight into how you are responding to training and external stressors.

Cons

Unfortunately, heart rate can be affected by several factors, such as stress, hydration, sleep, and medications, which may cause variations in the heart rate measurements. It is also less reliable in some environmental conditions, such as extreme temperatures, altitude, or high humidity.

Furthermore, the measurement is not as precise as the power output in cycling. The heart rate measurement is lagging as it estimates the energy used and is not an exact measure of the work.

We suggest you use more than one way to measure your training intensity. And be aware of possible biases and external factors that may affect the results.