Shackling and confinement in a small space (generally used to create discomfort and muscle fatigue) were also part of the CIA program, but they were subject to stringent time and manner limitations.

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This reduces muscle fatigue and enhances productivity.

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Diagnosis is difficult, because early symptoms of fever, muscle aches and fatigue often are confused with the flu.

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Individuals may suffer from high levels of fatigue, muscle or heart weakness, diabetes, strokes, or vision and hearing loss.

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The symptoms of ME include chronic fatigue, muscle pains and migraine, but in extreme cases patients can develop a permanent physical disability.

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Some of the more common side effects of weight-loss surgery can be difficulty digesting starchy foods and protein, which can lead to other physical conditions including hair loss, fatigue, swelling and muscle weakness.

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How people interpret some of the physical sensations of exertion or fatigue, such as buildup of lactic acid in muscle or increases in body temperature, can also influence whether they stick with an exercise routine.

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