According to the principle of progressive overload, what should be done to improve strength or endurance?

The principle of progressive overload is a foundational concept in strength and endurance training. It revolves around the idea that in order to improve physical performance, the body must be consistently subjected to increased levels of stress or workload. This stress can come in various forms, such as heavier weights, increased repetitions, enhanced training volume, or greater intensity of exercise.

By applying more stress to the body, whether through resistance training or different forms of cardiovascular training, muscle fibers are stimulated to adapt and grow stronger. This adaptation occurs as the body responds to the demands placed upon it. When changes are made gradually and appropriately, individuals can enhance their strength, endurance, and overall fitness.

Rest periods and training intensity reductions do not align with the principle of progressive overload, as they would not promote the necessary adaptations in strength or endurance. Focusing solely on flexibility also diverges from the core goals of progressive overload, which is targeted at strengthening and conditioning the body's muscles and cardiovascular system. Therefore, applying more stress to the body is key to achieving ongoing improvements in fitness.