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Physical fitness

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Physical fitness is a state of health and well-being. It is the ability to perform various tasks in sports, occupations, and daily life.

USMC-Rich Froning Jr
USMC-Rich Froning Jr

Modern fitness describes how efficiently a body functions during work or leisure. It also includes the ability to resist hypokinetic diseases and improve immune system function. Achieving fitness requires proper nutrition, moderate-to-vigorous exercise, and sufficient rest. A formal recovery plan is also a key part of the process.

Historically, the definition of fitness has changed alongside human society. Before the Industrial Revolution, fitness was simply the capacity to finish daily chores without extreme fatigue. Around 1950, the term "fitness" grew ten times more common in Western speech. This change followed the Industrial Revolution and the events of World War II.

Take a Pride in Being Fighting Fit Art.IWMPST2889
Take a Pride in Being Fighting Fit Art.IWMPST2889

Today, fitness is often linked to physical attractiveness, which has fueled global equipment industries.

Scientists study fitness through different biological mechanisms. One major type is aerobic exercise, which improves cardiorespiratory fitness. This involves movement that raises the heart rate to increase oxygen consumption. A common way to measure this is through VO2 max, which tracks oxygen uptake. Examples include jogging, swimming, cycling, or using an elliptical trainer.

Barbora Zahlavova Strycova San Diego
Barbora Zahlavova Strycova San Diego

These activities build stamina and a strong cardiovascular base.

Another type is anaerobic exercise, which uses high-intensity movements for short periods. This type of exercise does not require the body to use oxygen for energy. It is used to build strength, speed, and power. Examples include weight training, sprinting, and interval training. Anaerobic work can increase the metabolic rate. This happens because of rising body temperature and excess post-exercise oxygen consumption, or EPOC.

Calisthenics, 1867. Granger Collection
Calisthenics, 1867. Granger Collection

Fitness also involves complex chemical processes within the body. Recent research shows that skeletal muscle acts as an endocrine organ. When muscles contract, they release substances called myokines. These myokines promote the growth of new tissue and assist in tissue repair. They also provide anti-inflammatory functions to reduce disease risk. Furthermore, physical activity can assist in treating anxiety and depression. It may also help people sleep better by building up sleeping pressure.

To see real improvements, exercise must follow specific training principles. These include overload, specificity, and progression. Overload means providing a demand on a tissue or function. Specificity means training for a particular task, like a marathon or a military test. Progression means increasing that demand over an extended period.

Without these, the body may not continue to develop.

Health organizations provide specific guidelines to ensure safety and benefit. The 2018 U.S. guidelines suggest adults perform 150 to 300 minutes of moderate activity weekly. Alternatively, they can do 75 to 150 minutes of vigorous activity. In the United Kingdom, 2011 guidelines also recommend at least 150 minutes of moderate aerobic exercise. Both sets of guidelines emphasize muscle-strengthening activities at least two days a week. They also warn that sedentary time, or sitting too much, can harm health.

Finally, fitness is often viewed as a holistic system. Many experts use a triangle to represent physical, emotional, and mental health. These three points are all connected to overall well-being. Training can be task-specific, such as preparing a swimmer with squats.

Whether for professional athletes or everyday people, fitness connects the body to the mind.

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🖼️ Images & Media (5)
File:USMC-Rich Froning Jr.jpg
USMC-Rich Froning Jr.jpg
File:Take a Pride in Being Fighting Fit Art.IWMPST2889.jpg
Take a Pride in Being Fighting Fit...
File:Barbora Zahlavova Strycova San Diego.jpg
Barbora Zahlavova Strycova San Diego.jpg
File:Participants with the Water Warrior class perform squats prior to entering the pool at Camp Foster, Okinawa, Japan, July 6, 2011 110706-M-VD776-004 (cropped).jpg
Participants with the Water Warrior class...
File:Calisthenics, 1867. Granger Collection.jpg
Calisthenics, 1867. Granger Collection.jpg
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