Any soft tissue is subject to injury including ligaments (linking bone to bone), tendons (linking muscle to bone or muscle to muscle) and of course the muscles themselves. The immediate reaction of the body is similar regardless of the type of soft tissue that has been injured and is known as the inflammatory stage of injury. Injury to this tissue usually involves the breaking of small blood vessels that results in bleeding at the injury site. This bleeding leads to the main stages of inflammation which are:
HEAT – chemicals released at the site of the injury cause dilation of the surrounding blood vessels in order to bring healing agents to the injury. The result is more blood and thus more heat.
REDNESS – this is also due to the increased blood now in the area.
PAIN – this is the result of the chemicals that have been released from the injured tissues as well as the increased fluid which causes pressure to be exerted on the nerve endings.
SWELLING – This is the result of the extra fluid in the area.
This inflammatory action lasts for 24-48 hours following an injury and is a necessary part of the healing process. However the body tends to overreact to sudden traumatic injury sending more chemicals and fluid to the area than is needed. This fluid contains proteins that turn into replacement scar tissue, and too much of this scar tissue can mean that the muscle, tendon or ligament may not return to full working order after the injury. This means a risk of reduced flexibility and the risk of re-injury. You might also have to have a nasty sports therapist break up this scar tissue at a later date, ouch.
Ice works because it cools the heat produced at this inflammatory stage but it also causes the blood vessels to constrict thus lessening the effects of the chemicals, blood and tissue protein.