- External load represents objective training data such as time, distance, speed or elevation difference: it measures the stimulus applied.
- Internal load reflects how the body perceives exertion: it includes heart rate, perceived fatigue, and physiological response.
- The total load is the integration of internal and external load: understanding the right balance helps to train effectively.
Every workout has an impact on our body. The extent of this impact depends on factors that affect it to a greater and lesser extent, which can be grouped into two macro categories:
- external load (or stimulus)
- internal load
The external load
It concerns all those data that are not strictly related to the person, such as distance, time, or accumulated elevation gain during training. External load is an objective measure.
The internal load
It is a figure that determines the level of effort it took to conduct the workout, such as heart rate. It is a value given to us by our body in response to physical activity.
The training load
To calculate it, you need to sum both internal and external loads: in other words, the total strain placed on the body over a given period. Understanding the right amount of workload isn’t easy, but it’s something you can learn with time, patience, and experience.
The importance of recognizing the signals
Every body responds differently to stimuli, which is why no approach can ever be universally valid. The management of loads, external and internal, varies from person to person. While our minds can sometimes be indecisive or uncertain, our bodies know best. The responses to a stressful situation due to intense training are twofold: either the body responds in kind and comes out fortified, or it lets go and comes out debilitated. These are the signs you need to learn to assess whether you are training in the right way, or whether perhaps you need to make some adjustments.