Excerpts — Periodization Training for Sports-3rd Edition
Progressive overload is the favorite modality for eliciting morpho-functional adaptations through a progressive increase of muscular, metabolic, or neural stress over time. There are many ways to rationally progress the load and thereby elicit the desired adaptations, such as higher levels of hypertrophy, muscular endurance, maximum strength, or power.
Systematic strength training produces structural and functional changes, or adaptations, in the body. The level of adaptation is evidenced by the size and strength of the muscles.
Coaches without real knowledge of energy systems often intuitively develop programs that train the dominant energy system for their sport. For instance, sprint coaches intuitively train their athletes with sprint distances even though they are unfamiliar with the benefits of such training on the nervous system and the anaerobic energy systems.