Paramyotonia Congenita victims suffer from muscle stiffness which is worsened by muscle activity. (In contrast to those with Myotonia Congenita, who sometimes find improvements when they use their muscles.) Those affected have attacks of weakness or even paralysis. They can have trouble breathing because of having a tight chest which reduces the movement of the lungs. Cold conditions can cause muscle stiffness in everyone, even if they are not affected by this conditions. Those with it have a dramatic reaction to extremely cold temperatures- weakness lasting up to seven hours! Long term, this condition decreases muscle strength which in turn results in decreased muscle function.