The physician and natural scientist Georg Kunitz (1728-1796) already used the term ‘physical hardening’ in the 18th century. By this he refers to ‘the body’s habituation to being able to withstand weather influences and other complaints’ and he recommends measures such as cold showers and showers, walking barefoot and taking a sauna.
The principle of alternating cold and heat stimuli was adopted again a century later by spa physician Sebastian Kneipp (1821-1897). The idea is simple: the cold stimuli train the blood vessels, which improves temperature regulation in the body. This makes you less sensitive to the cold, you no longer freeze as quickly and you feel fitter.
However, the fact that you can harden yourself against the cold does not automatically mean that the measures protect against infections. Because it is neither scientifically proven that cold promotes infections nor that it protects against diseases.
There are many ways to get tougher. Especially hardcore people jump into lakes or the sea when the temperature is below zero. However, winter swimming fun is only suitable for people with stable blood circulation, a healthy heart and no vascular diseases.
“Inexperienced people should definitely approach the cool temperatures slowly,” says Professor Ingos Froböse from the German Sports University in Cologne. Alternating showers or Kneipp treatments are suitable for this purpose to allow the body to get used to the cold stimuli.
It is also advisable not to jump into cold water, but to enter it gradually. To prevent the body from cooling down too much, the bath should only last a few minutes. And very important: never swim alone in ice-cold water, but always with someone!
But does cold shock actually help protect yourself against colds? “So far, there is no clear research evidence that regular ice baths strengthen the immune system,” says Froböse. The only thing that is certain is that when you immerse yourself in ice-cold water, the blood vessels in the skin constrict and the blood vessels in the body dilate, helping the body to maintain its core temperature. This strengthens the cardiovascular system. Stress hormones are also released. They provide a special kick and high feeling after the bath.
Walking barefoot on dewy grass or fresh snow is a proven Kneipp paving measure. It strengthens the immune system and activates the blood circulation. What makes the measures effective is mainly their blood circulation-promoting effect, which also affects the mucous membranes. It means that cold viruses are less likely to attach to the nose or throat. In addition, the increased blood circulation has a refreshing effect when you are physically and mentally tired.
There are also rules to follow when walking barefoot on snow and wet meadows: To prevent hypothermia, stepping on the dew should not last longer than five minutes. As a guideline for snow running, beginners should initially limit themselves to a few seconds. Experienced people, on the other hand, can walk around in the snow for up to three minutes.
The feet should then be dried and quickly wrapped in socks and shoes. A tingling sensation of warmth, which usually appears quickly, indicates that the measure has worked.
Occasionally you see joggers in winter doing their laps in shorts or T-shirts. As long as the athletes are already hardy and keep moving, this is still okay in mild winter temperatures – but not in freezing conditions. “It makes sense to start running when it’s a little cold, so that you don’t sweat too much when you exert yourself; after all, your body warms itself up when you run,” says Froböse. “However, running in shorts and a T-shirt in temperatures below freezing is not a good idea, because the cold increases the risk of injuries to tendons, ligaments and joints.”
Less experienced runners generally need to adjust to the cold slowly, giving themselves a chance to warm up and keep their legs warm. When jogging in winter, you should also breathe through your nose if possible and keep your mouth closed. Doctors also advise people over 40 years of age or with previous heart disease to discuss sports activities with a doctor.
To ensure that jogging in winter is good for your health and strengthens your immune system, you need to follow a few important rules. “Before you start running, warm up and start at a moderate pace so that your body can get used to the load,” says Froböse.
When it comes to sportswear, the expert recommends the “onion principle” with several layers of clothing on top of each other. “It is advisable to initially wear breathable sports underwear that can absorb body sweat and keep the skin dry. Depending on your taste, wear a warm running shirt or fleece over it.” A running jacket made of functional fibers offers good protection against wind and moisture.
In very cold temperatures, runners should wear both gloves and a hat because people lose most of their heat through their heads. At temperatures below zero, Froböse recommends wearing a thin cloth over your mouth. “It humidifies and warms the cold air we breathe and protects the lungs.”
But you don’t necessarily have to jog in the freezing cold to become more resilient. Hardening can also be achieved through other sports. “When you exercise, you not only do something for your well-being, but you also strengthen your immune system and are less susceptible to infections,” says Froböse. The reason: “The adrenaline released during physical exertion leads to activation and proliferation of our immune cells.”
However, you shouldn’t overdo it. After very intense stress, the so-called “open window effect” can occur. “In this phase, our immune system is briefly weakened and viruses and bacteria have an easy time.” To strengthen the immune system, the sports scientist recommends moderate endurance sports, such as moderate jogging, walking or cycling, that do not put the body under extreme strain.
In addition, regeneration times should be planned between sporting activities so that the body can recover. If you have a fever, physical exertion is usually taboo. Otherwise, a flu-like infection can lead to life-threatening myocarditis. Before you are fever-free for at least three days, you need to take it easy.
The more regularly the body is exposed to cold stimuli, the less sensitive it becomes. A simple measure is to take a cold shower in the morning. To help your body cope better with cold shock, rinse your legs and arms first, then your torso.
To date, it has not been clearly proven whether cold showers actually train the immune system and prevent colds. However, scientists from the University of Jena were able to demonstrate in a study that regular cold showers on the upper body stimulate the immune system. The study participants then had 13 percent more immune cells in their blood than before. In addition, they had a lower frequency of infections than before or during the castings.
A gentler option to improve resistance is alternating showering. They also promote blood circulation and train the blood vessels. The process, which must be repeated three times, starts with a hot shower and ends with a cold shower. Rinsing with cold water should also start with the feet and arms. Just as with cold showers, regularity is also important when taking alternating showers.
source: watson
I’m Maxine Reitz, a journalist and news writer at 24 Instant News. I specialize in health-related topics and have written hundreds of articles on the subject. My work has been featured in leading publications such as The New York Times, The Guardian, and Healthline. As an experienced professional in the industry, I have consistently demonstrated an ability to develop compelling stories that engage readers.
