Heat loosens the muscles and relaxes the body and mind. In physiotherapy it is used to loosen the tissue before manual intervention. © Copyright Vakker Products GmbH
Heat therapy is traditionally used in physical therapy to relax muscles. This side-effect-free and natural form of therapy has a long tradition and is also popular in traditional Chinese medicine (TCM). Why heat therapy is so effective, how you can use it to strengthen your health and relieve tension - you'll find out all about it in this article.
What exactly is heat therapy?
Along with cold therapy (cryotherapy), heat therapy is a sub-area of thermotherapy, which in turn is subordinate to manual therapy in physiotherapy. Heat treatments are also part of the standard repertoire in traditional Chinese medicine. It works by activating and supporting the body's self-healing powers .
For example, hardened tissue is loosened, which is why heat therapy is often used as a preparatory measure for further movement therapy methods or massages in physiotherapy. But heat therapy doesn't have to hide on its own either, because it improves blood circulation, which accelerates healing-promoting metabolic processes .
How does heat therapy work?
The relaxing and healing effects of heat therapy are based on the body's own temperature regulation mechanisms. To function optimally, we need a body temperature of 37°C, which can fluctuate by around 0.5°C throughout the day. How important this temperature continuity is can be seen from the fact that below 28° C and above 43° C it can even be life-threatening.
When external cold is applied, blood flow is prioritized to the internal organs. The veins narrow and blood pressure rises. © Copyright Vakker Products GmbH
Temperatures as low as 38°C are considered fever. so the body is quite motivated to maintain its temperature. If it gets too cold, he first tries to supply heat to the internal organs that are essential for survival. The little toe can then see where it stays.
What does the body do then? It constricts the blood vessels so that the blood can no longer be transported as easily to the outer regions of the body. This causes blood pressure to increase - a stressful condition. In addition, it tenses the muscles, also in an attempt to produce heat. And if all that isn't enough, muscle contractions, also known as tremors, follow.
When it is warm, the body tries to direct heat away from the internal organs to avoid overheating. It widens the veins so that blood flows better to the entire body. Blood pressure drops. © Copyright Vakker Products GmbH
The opposite happens when external heat is supplied, for example through high outside temperatures in summer, through a hot bath, a sauna session or the use of a heat pad. The body notices that heat is now available in abundance. As a result , the blood vessels expand, because now it's "party time" for all areas of the body, including the little toe. The blood can now flow better and the blood pressure drops - we relax. That's why a hot bath, a sauna session or even just a hot drink has such a soothing and stress-relieving effect.
Heat therapy not only has a relaxing effect, but also loosens tense muscles and accelerates healing processes. This is due to a positive side effect of the widening of the blood vessels. Because the blood can flow better, the cells in the warmed areas of the body are better supplied with nutrients. In addition , metabolic waste products are removed more quickly. Both together ensure faster regeneration of the tissue - be it sore muscles after training or simply tense muscles.
Areas of application of heat therapy
In general, heat can be used for all "physical ailments" that are not acutely inflammatory - i.e. where improved blood flow and thus metabolism is beneficial. In the case of an open wound or a bruise, but also in the case of inflamed joints (for example due to rheumatism), this would be counterproductive, as this would only allow the inflammatory substances to spread even more easily. In such cases it is best to intervene with cold.
A popular area of application for heat therapy is tension, as the heat improves blood circulation and reduces muscle tension. © Copyright Vakker Products GmbH
Heat therapy for tension
Whenever connective tissue, fascia or muscles harden, you can counteract this with heat. The most common applications are for:
Abdominal pain (e.g. during menstruation in women or as a result of irritable bowel syndrome)
Because muscle tension and blood pressure decrease when exposed to heat, the body and mind relax. © Copyright Vakker Products GmbH
Heat therapy as a means to combat stress
The generally beneficial, stress-reducing effect of heat should not be underestimated. In order to explain where this relaxing effect comes from, a short excursion into evolutionary biology follows.
To ensure that our chances of survival in the face of occasional saber-toothed tiger attacks and food shortages millions of years ago were not reduced to zero, we, like other vertebrates, were able to use two "counterparts" in the central nervous system.
We are talking about the sympathetic and parasympathetic nervous system. The sympathetic nervous system switches on in stressful situations. Our pupils dilate, our muscles are tense and our heart beats faster. If the saber-toothed tiger ran away because it saw a juicier piece of meat, the parasympathetic nervous system slowly becomes active.
Now it's time to rebuild the resources that have been used up. The muscles relax, the blood vessels expand and blood pressure drops. But what does this have to do with heat therapy? Externally supplied heat allows us to trick the body, so to speak. Anyone who has ever heard of "power posing" or the possibility of improving one's mood with a simple smile can certainly imagine something about the interaction between body and psyche.
As explained above, heat causes our blood capillaries to dilate and blood to flow better. Blood pressure drops. And when blood pressure drops, we relax. The body doesn't really care about the chicken-and-egg question of which came first. The result counts.
So if you are once again plagued by the modern saber-toothed tiger in the form of 100 unanswered emails, run yourself a hot bath or take a heating pad and switch your nervous system into relaxation mode.
Heat therapy at home
There are a whole range of options for heat therapy at home. We present the most effective, user-friendly options to you below in descending order.
A hot bath can fight viruses by causing an "artificial fever." It also loosens the muscles all over the body, speeding up regeneration if muscles are tense or sore. © Copyright Vakker Products GmbH
A hot bath
It's not just the relaxing and blood pressure-lowering effect of whole-body heat that makes you want to go swimming again. At a temperature of 38°C or more, a type of “artificial fever” is caused.
That doesn't sound particularly attractive at first, but it has some advantages. This condition causes increased production of white blood cells. Those that support the immune system in defending itself against viruses and bacteria. A hot bath (or even a sauna session) can effectively prevent illnesses. You can also achieve a variety of other positive effects with the right bath additives, from protecting and building up the natural skin barrier to stimulating the circulation.
Local heat therapy with moor cushions specifically loosens tense tissue and accelerates regeneration. Same effect as in the bathtub, only locally. © Copyright Vakker Products GmbH
Heat therapy with mud pillows
Maybe you have already heard about mud therapy or the mud pack during physiotherapy or, better yet, experienced it yourself. The heated mud or mud mass is applied to the affected area to loosen and relax muscles and tissue.
Why do you use mud and mud for this and not a simple grain pillow? This is due, on the one hand, to the better heat storage capacity and, on the other hand, to the temperature conduction speed. Because the temperature of natural moor is transported at a similar temperature to human body tissue, a higher temperature feels more comfortable.
And a higher temperature means more effective loosening. We illustrate exactly how this works and why this is the case here: The healing effect of mud pillows in heat therapy.
So that you can benefit from this effect at home, there are moor pillows, for example for the neck or back. Depending on the quality of the moor, the processing and the quality of the film, if used and stored correctly, you can reward yourself with a relaxing, health-promoting wellness treatment at home every day for around two years.
If you go out of the house, heat patches are a good option for acute pain. However, if used regularly, it quickly becomes expensive. © Copyright Vakker Products GmbH
Heat therapy with heat patches
The main advantage of heat patches is that you can use them almost anywhere . Heat is created through a chemical reaction of the ingredients (usually a mixture of iron, salt, carbon and water) with oxygen.
Using heat patches helps many people, as the therapeutically necessary temperature of at least 40°C is reached and can be maintained for a relatively long time. However, occasionally skin irritation occurs due to the ingredients and with an average application price of around €4, it can quickly become expensive if used regularly.
For cozy warmth and mild stomach aches, cherry stone pillows are a good choice. If you want to relieve tension, a hot bath or heat therapy with mud pillows are more recommended. © Copyright Vakker Products GmbH
(Homemade) heat pads with grain filling
Grain pillows are probably the best-known representatives among heat therapy utensils. Whether it's a cherry stone pillow or a spelled pillow, most people have something like this at home or have at least heard of it.
You can buy grain pillows relatively cheaply or, with a little time and sewing skills, you can easily make them yourself. These heating pads are particularly suitable if you just want a pleasantly warm feeling when going to bed or reading .
However, if you want to relieve tension, grain pillows are not the best option. The temperature evaporates relatively quickly and cannot penetrate as deeply into the tissue because the application area is many times smaller due to the small, individual grains than with full-surface applications such as mud therapy or with mud cushions.
The hot water bottle is also primarily suitable for cozy warmth and not so much for tension. © Copyright Vakker Products GmbH
The good old hot water bottle
The hot water bottle may take some of us back to childhood - rusks, cola and a hot water bottle, that was the secret recipe for any aches and pains in the gastrointestinal area. Even if the use of rusks and cola is rather questionable in terms of health these days, the hot water bottle definitely had and still has its place.
It can have a relaxing and relieving effect on mild stomach pain and, above all, when snuggled up in a blanket, it creates a pleasant feeling of coziness.
When should you not use heat therapy?
Basically it can be said that heat therapy is out of place for all inflammations. This is, for example, an open wound or a swelling or a bruise.
Since the bloodstream expands due to heat, the inflammatory substances can spread more easily, which results in the inflammation increasing. It's like adding fuel to the fire. Cold is more suitable here, as it constricts the bloodstream and thus curbs the inflammatory process.
Frankfurter Allgemeine Zeitung: It warms your heart, 2013
Mitteldeutscher Rundfunk: Relieve pain: All-round health through warmth, 2018
Doccheck: Heat Therapy, 2021
Ranker, A. et al.: ELSEVIER ESSENTIALS - Medicines and medicine regulations, Elsevier/Urabn & Fischer Verlag, 2019
Quality Assurance Working Group of the Society of Medical Assistant Professions for Rheumatology: Guidelines for Physiotherapy, 2006