When your duvet causes muscle stiffness

Waking up with tense muscles in the morning? The culprit could be something you didn’t even suspect – your nice and cosy duvet. — dpa

Do you snuggle under a thick eiderdown when you go to bed in your air-conditioned room?

Well, you may regret it, because if you get too toasty under your duvet, you could wake up with stiff muscles.