What causes severe muscle tightness and back pain every morning?

Brief Answer:
First, we begin with pain

Detailed Answer:
First there are the questions one would ask about any pain:
localization. If the pain is inside, and affecting breathing and associatd with shortness of breath that is waking someone up, this is a pretty typical (and serious) symptom of heart disease. On the ohter hand if it isn't associated with breathing, but is triggered by moving/twisting and doesn't relate to breathing, and feels outside and like a muscle, then it isn't heart.

Stiff muscles after sleeping is quite common. Obviously trying different mattresses (does it occur when on vacation and staying at a hotel that use commercial Very Stiff Mattresses) would not only indicate that it isn't a serious condition, but wold also show how to fix it!

Muscle pain that is only part of the day, especially if it is not worse by the end f the day is not likely to be due to a serious underlying condiion and aspirin, muscle relaxants, will likely help. (also perhaps chiropracty and/or physical therapy)

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