Chi normally circulates within the body through lines called Meridians. (this concept is not accepted by Western Medicine - but this is not the point).
If a Meridian is blocked or interrupted (by a cut, an hematoma, a bent limb), the flow of Chi through it is interrupted. One speaks of "Chi Stagnation". The result is a poor irrigation of tissues and organs. Tis, in the short term results in local pain, and in the long term, if not addressed, internal organs might be damaged, and their functions hampered.
For TCM Blood nourishes the body, moistens body tissues and ensures that they do not dry out. Blood and Chi are interdependent and perform many of the same functions.
But Blood also contains Shen (Japanese Shin, Kokoro), or spirit, which balances the psyche.
Which is why we practice Kinhin - walking meditation - between sitting periods.
Proper meditation practice should incorporate exercises promoting Blood and Chi circulation, while at the same time harmonizing the Shen.
Conversely, proper martial art practice should incorporate Spiritual discipline to avoid mindless emphasis on Physical accomplishment - but this is an other story...