Final answer:
The principle of applying an incremental load that exceeds the muscle's current capacity to improve performance is called progressive overload. This principle is essential for muscle growth and requires gradually increasing exercise intensity to prevent injuries and allow for recovery.
Step-by-step explanation:
To improve muscle performance, the principle that a load which exceeds the metabolic capacity of the muscle must be applied is known as progressive overload. This concept is crucial for effective strength training, as performing a static level of exercise without increasing intensity will not lead to improvements in muscle size or strength.
When you lift weights that are heavier over time, you create a challenging environment for your muscles, forcing them to adapt, grow, and gain strength. This adaptation comes following principles such as isotonic contractions—where muscles shorten to move a load, and isometric contractions—where muscles generate tension against an unmoving load. However, it is important to increase the load gradually to prevent injuries and to ensure proper muscle recovery.
Additional structural proteins repair any muscle fiber damage incurred during exercise, which not only helps in muscle building but also contributes to the muscle's soreness. Overlooking these safety measures could lead to overuse injuries, tendon damage, or even bone damage if loads are too heavy.