Some people tend to read such physical cues as a sign of a good workout or progress, whereas many sedentary people just find them uncomfortable or painful, say researchers.

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When the cause is found, cramping can be due to prolonged sitting or leg position during sedentary activity.

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Single chamber ventricular pacing is considered an acceptable alternative in sedentary patients or those in whom technical issues make atrial lead placement difficult or impossible.

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Whether slim or fat, a person leading a sedentary lifestyle has similar chances of dying young to a smoker.

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Also consider limiting other sedentary activities, such as text messaging or chatting on the phone.

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In fact, three Big Macs, or 1, 450 calories, is a quite strict daily diet for a sedentary adult male.

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But many sedentary people push beyond their intrinsic range when they try to exercise too quickly or intensely, which can make them hate the activity and want to stop, says Dr. Ekkekakis.

WSJ: Hard-Wired to Hate Exercise?

Sitting reading is a sedentary occupation, and yet no-one is suggesting you should avoid "War and Peace" or the later, over-long Harry Potter novels.

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