One of the most common questions I hear from patients is, “When should I use ice and when should I use heat?” Using a hot water bottle or heating pad over the surface of the skin conducts heat into the target area and increases blood flow. The increased circulation helps relax and loosen tissues, particularly as the heat penetrates down into the muscle. This is why many patients report that taking a hot shower in the morning helps decrease muscle stiffness.
Heat applications are best used at least two days after an initial injury or for chronic muscle tightness. Localized applications of heat placed on the surface of the skin for not longer than 20 minutes at a time allow the heat to penetrate deeper than the surface of the skin. The heat helps increase flexibility and decrease muscle spasm and tightness
Applications of heat are an easy and inexpensive home treatment. Used properly, heat can be an important part of your treatment program and help you relieve back pain. There are several ways to apply heat: electric heating pads, hot wet towels, microwavable bean bags/gel packs, hot water bottles. The heat should be applied for not longer than 20 minutes over one particular area. After an hour heat can be reapplied. There should be a layer of towel or cloth between the skin and the heat source. Hotter is not better; the idea is to let the heat penetrate into the tissue, not to burn the skin. Repeatedly check the area for excessive redness or irritation of the skin. Never apply heat while sleeping or lay on top of a heating pad. Excessive heat will cause too much swelling in the tissue.
If the area of your pain is swollen, bruised, or the injury occurred within the past 48 hours, do not apply heat. Additionally, some patients try to soak in a tub of hot water. Unfortunately, it is difficult to maintain a normal curve in the lower back when sitting in a bathtub. This can aggravate lower back pain.