Memorizing all of the parts of the OPT model isn't necessary. Memorize some of the key bits, review the tables, learn the patterns, and be ready to answer multiple choice questions.
A traditional method of program design that aims to gradually increase the intensity of the training load while simultaneously decreasing volume over a set period of time
The aerobic system has other components like the Krebs Cycle and Electronic Transport Chain that can power the body for a long period of time (endurance events)