Endurance

Endurance (also related to sufferance, forbearance, resilience, constitution, fortitude, persistence, tenacity, steadfastness, perseverance, stamina, and hardiness) is the ability of an organism to exert itself and remain active for a long period of time, as well as its ability to resist, withstand, recover from and have immunity to trauma, wounds, or fatigue.

The term is often used in the context of aerobic or anaerobic exercise. The definition of "long" varies according to the type of exertion – minutes for high intensity anaerobic exercise, hours or days for low intensity aerobic exercise. Training for endurance can reduce endurance strength^{[verification needed][1]} unless an individual also undertakes resistance training to counteract this effect.

When a person is able to accomplish or withstand more effort than previously, their endurance is increasing. To improve their endurance they may slowly increase the amount of repetitions or time spent; in some exercises, more repetitions taken rapidly improve muscle strength but have less effect on endurance.^[2] Increasing endurance has been proven to release endorphins resulting in a positive mind.^{[citation needed]} The act of gaining endurance through physical activity decreases anxiety, depression, and stress, or any chronic disease^{[dubious – discuss]}.^[3] Although a greater endurance can assist the cardiovascular system this does not imply that endurance is guaranteed to improve any cardiovascular disease.^[4] "The major metabolic consequences of the adaptations of muscle to endurance exercise are a slower utilization of muscle glycogen and blood glucose, a greater reliance on fat oxidation, and less lactate production during exercise of a given intensity."^[5]

The term stamina is sometimes used synonymously and interchangeably with endurance. Endurance may also refer to an ability to persevere through a difficult situation, to "endure hardship".

In military settings, endurance is the ability of a force^{[clarification needed]} to sustain high levels of combat potential relative to its opponent over the duration of a campaign.^[6]