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Fitness is defined as the quality or state of being fit. Around 1950, perhaps consistent with the Industrial Revolution and the treatise of World War II, the term "fitness" increased in western vernacular by a factor of ten. The modern definition of fitness describes either a person or machine's ability to perform a specific function or a holistic definition of human adaptability to cope with various situations. This has led to an interrelation of human fitness and attractiveness that has mobilized global fitness and fitness equipment industries. Regarding specific function, fitness is attributed to persons who possess significant aerobic or anaerobic ability, i.e. endurance or strength. A well-rounded fitness program improves a person in all aspects of fitness compared to practicing only one, such as only cardio/respiratory endurance or only weight training.
Employing a right mix of two or more of the aforementioned types of training can promote well-rounded physical fitness. For example, a combination of agility training and eccentric training is useful in sports that require strength, endurance, and coordination such as basketball and football. A combination of strength training and continuous training benefits individuals who want to maintain a certain type of physique.
Strength training is one of the five types of physical fitness training that revolve around building muscle mass and bone density, as well as improving the strength and endurance of muscles by inducing muscle contraction through the use of resistance. It also enhances the functions of the joints and develops the sturdiness of tendons and ligament, thus reducing the risk of injuries from physical activities.
People who are physically fit are also healthier, are able to maintain their most optimum weight, and are also not prone to cardiac and other health problems. In order to maintain a relaxed state of mind, a person should be physically active. A person who is fit both physically and mentally is strong enough to face the ups and downs of life, and is not affected by drastic changes if they take place.