Differentiating muscle stiffness and tension.Among therapists, muscle stiffness and tension are often used interchangeably. However, there are some key differences between the two. Muscle stiffness is a condition in which muscles cannot be moved quickly without pain. A variety of factors may cause muscle stiffness, including prolonged immobility, electrolyte imbalance, or metabolic conditions.  Muscle tension, on the other hand, is a change in the muscle … [Read more...]