As we have been learning, hydrotherapy is the use of water, both internally and externally to revitalize, maintain, and restore health. It is used in the treatment of disease and to alleviate pain.

Last month we reviewed the principles of hydrotherapy, and why the application of water, either hot or cold, can mediate a healing response from the body. This month we will look at various effects of hydrotherapy on the body, using either heat or cold. The following month we will look at specific hydrotherapy treatments, how and when to use them.


Water treatments use the body’s own defenses to promote healing. Water plays a different role in different kinds of hydrotherapy treatments, and each treatment has multiple effects affecting more than one body system at the same time. Water stimulates the skin, muscles, joints, internal organs, and nerves. As mentioned last month, water can promote the absorption of healing substances into the body through the skin. Some treatments produce their results through the nervous system. Most treatments affect the body using water temperatures above or below the human body temperature. Hot and cold water redistributes blood throughout the body, by either constricting or dilating blood vessels.


Often people ask, “Do I apply ice or heat to an injury?” When a sudden injury occurs, often there is bruising from broken blood vessels, swelling, inflammation and redness on the skin; sometimes pain is the only indication of an injury. Ice treatment is typically used with an acute injury, and should be applied as quickly as possible after the injury occurred; this is when icing is most effective in reducing inflammation. Ice should be used especially if the injury involves heat, redness, and swelling. The types of injuries that require ice are sprains, strains, overuse injuries, muscle contusions (usually from a direct impact to the muscle), or bruises. The cold limits the body’s response to the injury. With an injury, bleeding typically occurs in underlying tissues, which causes pain and inflammation, and can delay healing.

The body’s response to an injury is inflammation. The blood vessels and tissues swell to allow immune cells to access the site of an injury. It is a process that helps in healing, so icing needs to be done properly to allow this process to take place, but to also limit the amount of inflammation and pain that occurs, and the length of time that it occurs. If ice is not used, the amount of inflammation is increased and length of time of the inflammatory process lasts longer than necessary. Proper icing will reduce the amount of inflammation and the length of time with which it occurs. While vital to healing, inflammation left uncontrolled can lead to extreme pain and disability. Limiting swelling and inflammation will speed up the healing process.

Icing will reduce the pain of inflammation and reduce the swelling. The coldness of the ice reduces blood and other fluids from going into the tissues surrounding the injury by constricting blood vessels, making them smaller thus decreasing inflammation. Cold also reduces muscle spasms and pain by slowing nerve impulses to the area. It also reduces pain by numbing the area. Elevating the injured part of the body above the level of the heart during icing and even in between treatments, will further reduce pain, throbbing and swelling. Do not use heat on a new injury as it will increase bleeding by increasing the temperature of the skin and increasing circulation, making the injury worse.

Ideally, cold should be applied within 5–10 minutes of an injury. Cover the cold pack or ice in a towel so that cold does not come in direct contact with skin, otherwise it can cause a burn or frostbite. Another way to prevent frostbite is to continually move the ice around the area, called an “ice massage”, so that any one spot does not have prolonged direct contact to the ice. Check the colour of the skin after five minutes. If the skin is bright pink or red, remove the ice or cold pack. If not pink, the cold treatment can be applied for a further 5–10 minutes. The effect of the cold can be improved if it is pressed gently onto the injured area.

After the cold is removed, the blood vessels overcompensate and dilate. Blood rushes into the area and brings along nutrients necessary to heal the injured area. This is the rationale for short periods of cold. Not only does the cold restrict inflammation, but the subsequent removal of the cold will also assist with the healing process.

Never apply ice or cold packs for more than 20 minutes at a time, otherwise further damage can occur to the tissues surrounding the injury. If cold is left on for any longer, there is no benefit. In fact, it will cause the opposite reaction. If cold is used too long, it can drop the temperature of the area too low; it can restrict blood flow to the area and slow the healing process. Once the cold is removed, the body’s response will be to increase blood to the area, more than is healthy for healing. Repeated ice applications are helpful as inflammation and swelling can last for a few days. As long as the area of the injury is warm to touch and has normal sensation, one can ice as frequently as desired. However, allow the area of the injury to warm up for at least an hour before icing again.

Bruising and inflammation from an injury stops within 1–3 days, therefore the healing effects of ice decreases significantly when this occurs. Thus, when an injury is older than 48 hours, heat can be applied. Heat causes the blood vessels to dilate which brings more blood into the area, bringing with it healing nutrients. The aim of the treatment changes from restricting bleeding to getting the tissues moving with exercise and stretching. Heat has a direct soothing effect and helps to relieve pain and spasm, thus encouraging mobility after an injury.

Heat also is used for chronic injuries or on injuries that have no inflammation or swelling. For example, sore, stiff muscles or joint pain can be treated with heat. For people with chronic pain or injuries, such as with arthritis or old muscle strains, heat therapy can be used before exercise to increase elasticity of the connective tissues in joints, relax tight muscles or muscle spasms and to stimulate blood flow to the affected joint or muscle. It prepares the body for activity. Heat is also used to treat overuse injuries before an exercising.

Beware of icing muscle pain, which can increase stiffness. Only if a muscle has been actually injured, such as with a tear or a contusion, will ice help for the first two days. Many people who live with ongoing lower back or neck pain need to be mindful to use heat in these areas, as the muscles are in pain but are not “injured.”

Apply heat via a heating pad, microwaveable bag or steamed towels for 15–20 minutes at a time and use enough layers between your skin and the heating source to prevent burns. Use moderate heat; the heat should never cause sweating or discomfort. Moist heat provides better pain relief than dry heat by penetrating deeper into the muscle, and its effect works quicker. Never leave heat on for more than 20 minutes at a time or while sleeping, e.g. heating pad. With chronic injuries, never apply ice before exercise as it will stiffen joints and muscles. Also, do not use heat after exercise. Ice is better after an activity if one has a chronic condition that is prone to inflammation, such as with arthritis.

As a final warning, do not use hot or cold packs over areas of skin that is in poor condition; over areas of broken skin; over areas of skin with poor sensation to heat or cold; over areas of the body with known poor circulation; or in the presence of an infection. People with certain health conditions should not use heat therapy due to a higher risk of burns or complications. These include people with diabetes, dermatitis, vascular diseases, deep vein thrombosis, and multiple sclerosis.


Methods for applying whole body heat include hot baths, saunas, steam baths, and full body wraps. The effects on the body with whole body heat include: Skin temperature begins to rise; blood vessels near the skin dilate to try and get rid of the extra heat by increasing the flow of blood to the skin; this increases heat loss in the body through the skin; blood vessels of the internal organs constrict and decrease heat to those areas; ⅔ of the amount of blood that the heart pumps goes to the skin, which is up to six times as much as normal. When blood vessels dilate, it makes more room in the blood vessels, therefore blood

pressure drops. The heart rate increases to bring blood to the skin, up to 10 beats faster per minute with every degree the body temperature rises. Whole body heat can be used to help lower blood pressure, improve digestion, relaxation of joints and muscles, improve oxygen intake and overall breathing, balances hormone levels, and improves immune system function. When the body sweats, it naturally cleans itself by ridding the body of wastes through the pores of the skin.

One danger of full body heat is that much less blood is available to the brain. A person can become light headed. Breathing becomes quicker to rid the body of heat through the lungs. Because heat increases the number of white blood cells for several hours, heat is used to treat immune system disorders. Tendons, ligaments and muscles relax, decreasing the pain of tense tissues.


Methods for applying local heat include heating pads, steamed towels, and moist heating packs.

Localized heat is used for relieving muscle and joint pain. Effects of local heat include: Dilation of blood vessels in the area, which increases blood flow; local sweating; dilates blood vessels in muscles, which relaxes the muscle; increase in local metabolic rate; and increased oxygen delivery to tissues. Heat applied to one limb causes vasodilation of the other limb through the spinal cord; this is helpful if the area needing to be treated cannot tolerate direct heat. Heat also has reflex effects on the internal organs through the nervous system also. Nerves on the surface of the skin connect with organs deep inside the body. A hot foot bath can relieve a migraine headache because of the connection of the nerves in the foot to the nerves in the brain.


Our bodies can endure heat far better than cold. The body acts more vigorously to cold, making cold treatments more stimulating than hot. With an application of cold, the internal temperature of the body is protected by constricting blood vessels of the skin, preventing sweating, and increasing shivering. Constriction of blood vessels also increases blood pressure; the heart pumps more blood with each beat. A short cold application for approximately 1 minute, is invigorating. Full body blood vessel constriction floods the internal organs with nutrients and oxygen-carrying blood. The entire metabolism of the body is stimulated. Whole body cold treatments can be obtained by a using a cold shower or bath, or going into a cool pool or a lake.

Certain cultures, like the Finns in Finland, partake in winter swimming, and it is considered a traditional outdoor activity. Historical documents indicate that the Finns took cold-water baths as far back as the 17th century, and perhaps even before that time. Winter swimming clubs were initially founded in the 1920’s. Since then winter swimming as a health-enhancing physical activity has become increasingly popular.  Studies show that regular winter swimming significantly decreases tension, fatigue, memory, and negative moods with the duration of the swimming period; significantly increases vitality; relieves pain in those who suffered from rheumatism, fibromyalgia, or asthma; boosts the immune system; relieves stress and improves the general well-being of the swimmer. When the swimmer emerges from the water, the blood vessels react by dilating to return warmth to the skin. The person gets a prolonged sensation of warmth. Finns also improve on the health effects of winter swimming by first heating up in a sauna before jumping into a hole cut out from the lake ice. The alternating between hot and cold is healthier than just hot or cold on its own in invigorating the body.


Methods for applying local cold include ice packs, cold compresses, and cold, iced towels. Local cold is effective in producing numbness, reducing swelling and inflammation, and preparing healthy muscles and joints for movement. These reactions occur because of cold’s effects on blood vessels close to the surface of the skin. Local cold can also have a reflex action on the internal organs through the nervous system. Responses to cold depend on the initial temperature of the skin, how cold the treatment is, and how long it is left on. Local cold penetrates far more deeply than local heat. When a short cold application is used, it contracts the local blood vessels, decongesting tissues. This is rapidly followed by a reaction where blood vessels dilate and tissues are flushed with fresh, oxygen and nutrient rich blood when the cold is removed.

During a cold treatment, the nervous system increases the body’s levels of hormones. Vasoconstriction shuts off blood flow to local areas, decreasing bruising and inflammation. The deep internal blood vessels dilate as blood is directed internally. Constriction of muscle blood vessels takes place. Vasoconstriction of the opposite limb also occurs, via connections through the spinal cord. Regular local cold treatments causes blood vessels to increase tone and contract with greater force, enhancing circulation. Skin and muscle temperature decreases, and less oxygen is delivered to tissues. Muscle spasms decrease from a reduction in motor nerve activity. Connective tissues—ligaments, tendons—become stiffer. A reduction in the sensitivity of painful nerve endings can help ease pain from various ailments.


Alternating hot and cold treatments can be used as a whole body or local treatment. When using alternating heat and cold, combine heat treatments (vasodilation) with short cold treatments (vasoconstriction which then causes vasodilation) repeated 3 or more times. This combines the advantages of both hot and cold treatments.

Alternating hot and cold treatments have significant effects on the body: There is a dramatic increase in blood flow, at least double the resting amount. Reflex stimulation of related tissues and organs occur through the nervous system. With heat, muscles and joints relax, decreasing pain, but also causes congestion. Cold removes the congestion. It causes a strong feeling of invigoration. The increase in blood flow turns skin red. While heat increases circulation, it promotes congestion and edema; while cold decreases edema, it also decreases blood flow and deprives tissues of oxygen and other nutrients. When hot is combined with cold, local circulation is greatly increased without increasing edema. The amount of time that hot and cold is applied may vary (one example is 3 minutes hot and 1 minute cold). The use of alternating hot and cold treatments combine the advantages of each, without the disadvantages that arise from using only hot or cold.

As a general rule, a hot application or treatment should always be followed by a short cold treatment. The hot application expands blood vessels, filling them with blood. The cold constricts the area, so that blood moves away from the area, carrying waste from the area of the body that is inflamed, congested, or injured.


Short cold applications stimulate circulations (<1 minute). Long cold application (> 1 minute) depress circulation and metabolism. Long hot applications (> 5 minutes) depress both circulation and metabolism and leave the area congested and static. A cold application helps restore normality. Short hot applications (<5 minutes) stimulate circulation. A short hot application followed by short cold application causes alternating reactions in the blood circulation, followed by a return to normal.  Hot and cold treatments can be applied at differing temperatures, depending on the type of treatment.  Hot treatments typically range from 35–40C (96–105F). Cold treatments range from 10–21C (50–70F). The length of the treatment, and the part of the body being treated also need to be considered when deciding on the temperature of the water being used. Whole body hot and cold treatments should not be used at the extremes of either temperature.

Care needs to be taken when using hot and cold treatments. Both ice and heat have the potential to do harm when improperly used. Heat can make inflammation significantly worse. Ice can aggravate symptoms of both tightness and stiffness, which can also worsen any pain that is in the area being treated. Another problem to watch out for is applying heat and ice when the body is already in a state of excess cold or heat. Icing when you are shivering, or heating when the body is sweating sends wrong signals to the brain. Adding more heat or cold when the body is overheated or overcooled will trigger the brain to sense the added heat or cold as a threat and may react by worsening the condition being treated.

Full body heat should not be used with people who have heart conditions. Extreme cold and heat should be avoided in children or the elderly. Four principles need to be considered when using hydrotherapy: the type of treatment, the temperature of the water, the duration of the treatment, and the frequency. We will learn more next month on the safe use of hydrotherapy treatments.

Sister White visited the Paradise Valley Sanitarium, which was equipped with the latest and costly electrical instruments and mechanical fixtures in the treatment rooms. She later wrote to Br. Burden, who was in charge of the sanitarium, and counselled him on the use of the new treatment methods applied. “Several times I have been instructed that much of the elaborate, costly machinery used in giving treatments, did not help in the work as much as is supposed. With it we do not get so good results as with the simple appliances we used in our earlier experiences. The application of water in various simple ways is a great blessing.” –Loma Linda Messages, p. 178