How is strength defined?

Strength is defined as the ability of a muscle or muscle group to exert a force against a resistance. This definition highlights the physical capability of muscles to produce force, which is essential for various activities, from lifting weights to performing everyday tasks that require muscle engagement.

Understanding strength in this way encompasses various aspects of physical fitness, including muscular strength and endurance. For instance, when a muscle contracts and overcomes resistance—whether it's lifting a heavy object or pushing against a steady force—that is a direct application of strength. This definition is fundamental in exercise science and helps athletes and individuals to set training goals and assess their progress in strength-based activities.

The other choices relate to different components of fitness. Cardiovascular endurance refers to the efficiency of the heart and lungs in supplying oxygen during prolonged physical activity. Pivoting quickly relates to agility, which involves the ability to change direction rapidly while maintaining control. Flexibility pertains to the range of motion of joints and the length of muscles. Each of these areas is important for overall physical fitness, but they do not define strength specifically.