Strength

Strength is the capacity to exert or resist force. In physics and engineering, it describes how much stress a material can withstand before permanent deformation or failure, with measures such as yield strength and tensile strength. In biology, muscle strength is the maximal force that a muscle or muscle group can produce. In everyday language, strength can also refer to resilience or mental fortitude.

Human muscle strength depends on muscle mass, neural activation, fiber composition, and biomechanical leverage. It varies with age, sex, training, and health. Resistance training is the primary method to increase strength, often by progressively increasing load. Measurements include one-repetition maximum (1RM) tests and grip strength using dynamometers.

In materials science, mechanical strength is the ability to withstand stresses without failure. Key properties include tensile, compressive, and shear strength, often expressed in megapascals. Strength is influenced by composition, microstructure, temperature, and processing history. Failure can occur by yielding, cracking, or fracture.

Assessment and application: Strength is central to athletic performance, construction, and safety design. Training plans use progressive overload and recovery to improve strength, while inaccuracies can lead to injury. In design, engineers select materials with appropriate strengths for intended loads and environments.

Historically, understandings of strength have evolved from muscular power concepts to formalized measurements in physics and materials science. The term remains multifaceted, reflecting physical force, material properties, and psychological resilience.