The definition of intensity in muscle training according to training theory, refers to the selected resistance in relation to the repetition maximum (1RM). However, this article is about the vernacular use of the term. That is, your perception of how hard the workout feels.

The muscle changes when it is challenged beyond its current performance level. Through this stimulation we make the muscle understand that it needs to develop.

It requires a high level of mental readiness to reach an intensity level at which an effective muscle stimulus is set. The focus is simply higher in a short series. You will understand what is meant after the first series.

No. This is exactly the problem with most training programs. The workouts are almost always planned far too long. As a result, the focus is lost on each individual repetition. The intensity level for effective muscle stimulation is not reached.

Regular, very short muscle training is practical. The chance that you will stay on for the long term is very high. This is also because the effect of the workout can be felt quickly, and the motivation is rekindled daily.

For athletes with a very high level of fitness, it is becoming increasingly difficult to set an effective muscle stimulus. One possibility is to increase the training volume. Professional athletes have learned to permanently push the limits even during long workouts. Hobby athlete are far from this level.

A resounding yes. An amateur athlete should only undertake further exercises when he or she is sure that he or she can do the Big 5 with high intensity throughout the year.