PTs and doctors have commonly told clients that their muscles are 'tight' or your body is very 'stiff' but what really is being tight and stiff? I would define being tight or stiff as the inability to achieve certain range of motion whether passively or actively. For me, feeling tight or stiff can be used interchangeably. There are two types of tightness: structural and functional. Structural tightness involves your anatomy, some people are born less flexible than others and change is slow and will require the deformation of soft tissues. On the other hand, functional tightness is largely influenced by the nervous system (tone). This can be a protective response or something that is learned or adapted. For example, we develop a certain posture or joint position as a result of our work or through repetition. However, change is fast and involves the inhibition of tone. Having said that, functional tightness may lead to structural changes of the muscles, ligaments and joint alignments in the long term. Stay tuned for more next week!