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.
Calisthenics. There's nothing fancy about a calisthenics workout, but just because it's basic doesn't mean it's not effective. A 2017 study in Isokinetics and Exercise Science put a group of untrained individuals through a calisthenics program to test the effectiveness of an exercise method that uses no equipment. Participants did a brief workout consisting of four or five exercises three days a week for eight weeks. At the end of the trial, all participants had significant improvements in posture, strength and body composition.
Possibly one of the most important parts of fitness training is flexibility and mobility. Flexibility is the ability of your muscles to stretch, and mobility is being able to move your joints and tissues through their full range of motion. Both are important to athletic performance and for avoiding injury. Muscles and joints that are flexible and mobile — as well as strong — are much less susceptible to sprains and other injuries.
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.
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Eccentric training is another type of physical fitness training centered on improving eccentric muscle contraction. As a backgrounder, this type of muscle contraction occurs when the muscle elongates or lengthens from the influence of an opposing force. The contraction happens explicitly when a muscle gives in or goes with the flow or direction of an opposing force.
Centers for disease control and prevention provide lifestyle guidelines of maintaining a balanced diet and engaging in physical activity to reduce the risk of disease. The WCRF/ American Institute for Cancer Research (AICR) published a list of recommendations that reflect the evidence they have found through consistency in fitness and dietary factors that directly relate to cancer prevention.
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.
The Physical Activity Guidelines for Americans were created by the Office of Disease Prevention and Health Promotion. This publication recommends that all adults should avoid inactivity to promote good health mentally and physically. For substantial health benefits, adults should participate in at least 150 minutes a week of moderate-intensity, or 75 minutes a week of vigorous-intensity aerobic physical activity, or an equivalent combination of moderate- and vigorous-intensity aerobic activity. Aerobic activity should be performed in episodes of at least 10 minutes, and preferably, it should be spread throughout the week.
Physical activity boosts the immune system. This is dependent on the concentration of endogenous factors (such as sex hormones, metabolic hormones and growth hormones), body temperature, blood flow, hydration status and body position. Physical activity has shown to increase the levels of natural killer (NK) cells, NK T cells, macrophages, neutrophils and eosinophils, complements, cytokines, antibodies and T cytotoxic cells. However, the mechanism linking physical activity to immune system is not fully understood.