One of the most frequently asked questions of physiotherapists is: ice or heat?
Ice is for injuries — calming down damaged superficial tissues that are red, hot, and swollen. The inflammatory process is a healthy, normal, natural one that, unfortunately, also happens to be incredibly painful. Be careful not to ice too long, as frostbite can occur.

Heat is for muscles, chronic pain, and stress — taking the edge off of symptoms like muscle aching and stiffness.
Generally speaking, ice is for fresh injuries, and heat is for stiff, aching muscles. But it’s best to seek advice from your physiotherapist as to which is best for your condition.