You will find the term “RIR” in your training plans. This stands for “repetitions in reserve”. Translated: This is how many repetitions you should stay away from muscle failure, or how many repetitions you should leave “in the tank”. If you stick to these guidelines, you are training hard enough. The load increases over the course of a mesocycle.
If you are not sure how many more repetitions you could have done, do as many repetitions as you can with the specified weight. Each repetition above the target counts as 1 RIR. For example, if you do 14 repetitions instead of 10 in the test, your RIR is 4.
Consequently, if you do 10 repetitions with an RIR of 2, for example, you should not do more than 12 repetitions.