Application of heat, or cold; almost always in the form of advice given (and a hot/cold pack provided).

Heat: Directly stimulates Aβ sensory nerves, mimicking the effects of TENS. Heat also increases the metabolic rate of the tissue, mimicking the cellular excitation modalities. Heat can also directly increase extensibility of tissue, resulting in relief from muscle spasm, and increased range of motion.

Heat will any exacerbate bleeding &/ oedema locally. Possible side-effects include burning if too hot.

Cold: Cold, applied for up to 5 minutes, produces vasoconstriction, which will help to reduce bleeding and oedema in the early stages of the healing process. If applied for more than 5 minutes (but less than 15 minutes), cold has the opposite effect, improving the local blood flow which assist the healing process at all stages. If used little and often (approximately every 10 minutes, applied once every 90 minutes or so), the cold will improve the blood flow; but then, by removing the ice, the body's own regulation systems will immediately warm the area, exciting the cells, who can then use the extra blood supply provided. These vascular effects last longer after ice than they do after heat therapy. Ice also has an pain relieving (analgesic) effect through stimulation of the Aβ and Aδ sensory nerves, combined with the reducing the conductivity of the C (pain) sensory fibres (stimulating the A fibres out-competes the reduced conductivity).

If overused (more than 15 minutes per application, or more used frequently than every 60 minutes or so) then the use of cold therapy will slow down the healing process. Possible side-effects include an ice-burn if used inappropriately (ice-pack not wrapped in dry tea-towel).