In general, the compress made with ice is more indicated in cases of trauma caused by falls or blows. “The anesthetic action of the ice helps prevent swelling and bruising in the injured area from getting too big. The hot compress should be used in a second stage, about two days after the trauma. If it is a muscle strain, apply the hot compress five to seven days after the injury occurs. It helps increase blood circulation in the affected region, reducing the risk of inflammation,” says physiotherapist Emília Nozawa, from the University of São Paulo (USP).
There is also a third alternative, widely used in post-immobilization and post-surgery treatments: the so-called contrast. “After the person removes the cast, for example, or undergoes orthopedic surgery, the limbs – especially the lower ones – remain immobile, which causes slower circulation. For this reason, it is common to apply alternating hot and cold compresses, which end up working like a pump, stimulating blood circulation in the region”, says orthopedist Wagner Taffo Thomazin, also from USP.
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GOOD WARMTH
Warming up stimulates circulation and relaxes muscles
The warm compress causes blood vessels to dilate, increasing blood flow in the treated area. This helps contain the inflammatory process. If a hematoma or edema (swelling caused by extravasated fluid) forms, the heat softens the fluid that leaked from the vessels and accumulated around the affected area. This helps the body reabsorb fluid.
RECOMMENDATIONS AND SPECIAL CARE
Although the cold reduces both pain and swelling such as edema and bruises, it can harm very sensitive skin. Therefore, it is not advisable to use ice for more than 12 uninterrupted minutes. Between one application and another, there should be an interval of at least ten minutes. In addition, it is advisable to avoid using ice on open wounds and burns (in which case it is better to use cold water as an anaesthesia). Cold can also be used by athletes and gymnasts to prevent cramps and treat tension and fatigue.
FRIDGE BENEFIT
In addition to being an anesthetic, cold constricts blood vessels, reducing swelling.
1 – Traumas caused by falls or blows usually break the vessels of the blood and lymphatic systems. The leakage of these two liquids – blood and lymph – is responsible for the swellings (edemas and bruises) that appear after the injury.
2 – If ice is applied right after the trauma, the vessels contract, making the leakage flow much smaller and, consequently, the swelling and hematoma are also reduced. Furthermore, if the skin is cooled to 12ºC or 13ºC, the pain receptors stop working – hence the anesthetic effect of ice
RECOMMENDATIONS AND SPECIAL CARE
Heat is indicated in cases where the person feels pain but does not have swelling. An example is the beginning of a toothache, when the inflammation has not yet worsened, but the suffering is already considerable. The same goes for cases of rheumatism and tendinitis. Depending on the area where it is applied, heat can both improve breathing and reduce acid secretion in the intestine, relieving kidney pain and stimulating urine production. Hot compresses also help fight menstrual cramps, due to muscle relaxation in the belly region.
MIXED TECHNIQUE: CONTRAST
Alternating hot and cold equals a massage
There are cases where the best choice is not to adopt isolated temperature extremes, but a combination of both. The so-called contrast therapy uses the alternating application of cold and hot compresses to then contract and then dilate the blood vessels, increasing circulation in the affected area. The technique is especially indicated for infections, strains, inflammations and headaches caused by nerve or muscle tension.