What is defined as being able to maintain a certain level of fitness with less effort once achieved?

The concept of maintaining a certain level of fitness with less effort once achieved is best captured by the term "maintenance of fitness." This refers to the ability to sustain the fitness levels gained through training without requiring as much exertion or intensity as was necessary to attain them initially. Once a particular fitness level is reached, individuals often find that they can maintain those levels through less frequent or less intense workouts, allowing them to balance their fitness routine with other demands in their life.

In contrast, performance optimization focuses on maximizing athletic performance, often involving rigorous training regimens. Endurance fitness typically relates to the ability to sustain prolonged physical activity, while a fitness plateau refers to a period during training where no further improvements in fitness are observed despite continued efforts. These concepts are related to different aspects of physical activity and fitness but do not specifically address the idea of maintaining fitness levels with decreased effort after reaching a certain point.