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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.
A comprehensive fitness program tailored to an individual typically focuses on one or more specific skills, and on age- or health-related needs such as bone health. Many sources also cite mental, social and emotional health as an important part of overall fitness. This is often presented in textbooks as a triangle made up of three points, which represent physical, emotional, and mental fitness. Physical fitness can also prevent or treat many chronic health conditions brought on by unhealthy lifestyle or aging. Working out can also help some people sleep better and possibly alleviate some mood disorders in certain individuals.
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.
For physical fitness activity to benefit an individual, the exertion triggers a response called a stimulus. Exercise with the correct amount of intensity, duration, and frequency can produce a significant amount of improvement. The person may overall feel better, but the physical effects on the human body take weeks or months to notice and possibly years for full development. For training purposes, exercise must provide a stress or demand on either a function or tissue. To continue improvements, this demand must eventually increase little over an extended period of time. This sort of exercise training has three basic principles: overload, specificity, and progression. These principles are related to health but also enhancement of physical working capacity.
To exercise, work, do daily chores and play sports, you’ll need varying levels of cardiorespiratory capacity and stamina, muscle strength and endurance, footwork skills and speed. Training for one type of fitness often requires different types of exercises than training for another type of fitness. For example, strength training uses heavy weights and slower muscle movements than sprint training, which is performed with little resistance and high-speed muscle movements. These different types of fitness workouts recruit different muscle fibers and burn different amounts of fat and glycogen. It's best to focus on strength and endurance exercise during a sport off-season, and work on speed and recovery during the preseason and in season.
New (July 2011) guidelines in the United Kingdom include the following points: The intensity at which we exercise is key, and light activity such as strolling and housework is unlikely to have much positive impact on the health of most people. For aerobic exercise to be beneficial it must raise your heartbeat and make you sweat. The more exercise you do, the better. Everyone should do a minimum of 150 minutes a week of moderate-intensity aerobic exercise but that really is the minimum for health benefits. If you can go beyond 150 minutes, you’ll gain even more health benefits. Sedentary time (time spent sitting down to watch TV, use a computer, read or listen to music) is bad for your health, even for those who are achieving 150 minutes of exercise a week. These guidelines, are now much more in line with those used in the US, also include recommendations for muscle-building and bone strengthening activities such as lifting weights and yoga.