Note to the reader:  This blog provides detailed fitness information. 

Our chance for improvement is sometimes called a “Window of Adaptation.” When you are just starting something you have a very large window of adaptation. When you are new to something you are going to see big improvements. But as you make improvements your window of adaptation becomes smaller, this analogy holds true for fitness.  So when you become more trained and you get closer to your genetic potential changes are harder to see.

So when your window becomes smaller, training efforts need to be targeted and intentional to see improvement. Make sure you consider your exercise selection, exercise progression, volume changes and even rest intervals.

Rest intervals between sets determine the amount of energy stores that are re-synthesized. It takes more time for some energy sources, such as ATP-PC, to become restored than others. More rest between sets is needed when working absolute strength versus dynamic strength, but recent research has shown an interaction of the window of adaptation and rest.

Research found that shorter rest intervals can be effective for strength increases in less trained individuals, muscles or exercises. New areas or exercises, or those coming off of a break were shown to need shorter rest intervals between sets.  And longer rest intervals were shown to “become increasingly important as the potential for continued strength increases diminishes over time for a given exercise.”1

As you begin or start back up on a strength training regiment, take advantage of the window of adaptation in using shorter rest intervals and experiencing rapid gains. But it is important to remember that you are building a foundation so this is a good time to pay attention to form and technique. As training progresses, activities will need to be more specific to achieve goals and rest intervals.

1Salles, B.F., et al. (2009). Strength Increases in Upper and Lower Body are Larger with Longer Inter-set Rest Intervals in Trained Men. J Sci Med Sports. October 2009.