“This study suggested a new workload efficiency index, where the external load consisted of the equivalent distance and a modified training impulse. As the authors described, the equivalent distance “represents the distance that a player would have covered theoretically at a steady pace on grass using the total energy spent over the match or training”.
After calculating the match workload efficiency index, the authors analysed how different locomotive measures affected this index. Personally, I think that care must be taken when utilising such models, as they don’t account for possible heart rate responses to psychological factors (e.g. match-related stress, environmental factors (e.g. air temperature, humidity and height above sea level) or nutritional strategies (e.g. caffeine intake). Furthermore, the analysis used in this study provided a team average based model, neglecting important non-training related factors, such as playing position or player’s age.
As a practitioner, I always like to understand what is interesting, important, or a determinant for an athlete’s or team’s success. I believe this index is interesting, but still far off to being used in a way that will affect any athlete or team’s training schedule.”