How is the principle of overload defined in physical training?

The principle of overload in physical training is defined by the concept of performing more than what has been previously done. This principle is fundamental to enhancing physical fitness and performance because it involves challenging the body beyond its current capacities and limits. When an individual continuously applies a higher level of stress on the body, whether through increased weights, more repetitions, or higher intensity, the body adapts over time by building muscle, increasing strength, and improving endurance.

Overload ensures that the training stimulus is sufficient to elicit physiological changes, which in turn promotes progress and avoids plateaus. It's essential to remember that overload must be applied progressively to prevent injury and ensure long-term improvements in fitness.

The other choices do not accurately reflect the principle of overload. Simply increasing the frequency of workouts may not necessarily constitute overload if the intensity and volume of those workouts do not increase accordingly. Longer rest periods between workouts focus more on recovery rather than challenging the body. Decreasing exercise intensity over time contradicts the essence of the overload principle, as it would not promote adaptation or improvements in fitness.