What is still a tolerable temperature to go outside to train? Can being cold in sports do more harm than good? What should you wear for outdoor training in the cold?
It's true that in cold weather, even lighter exercise is just as taxing as a high-intensity workout done in warm weather. In cold weather, sports increase the load on the heart and circulatory system - surface blood vessels expand, which increases blood pressure. In extreme cold, movement is also not enough to keep the muscles warm enough, so the function of the muscle tissue weakens substantially. Chilled limbs may feel stiff and exercise sticky.
However, a cold does not mean that you should stay lying on the couch. Light sports in the cold are suitable for almost everyone, and for an active person, stopping training like a wall can do more harm than good. However, moderation in everything, assess the conditions before training, prepare with sufficient layers of clothing and, if necessary, a respirator, remember to warm up sufficiently and take a warm enough drink with you.
What is the appropriate freezing point?
For fitness enthusiasts, the recommended frost limit is about -15 degrees. However, the appropriate limit largely depends on the type of exercise and the athlete's ability to get used to the cold. A leisurely cross-country run or a snowshoe walk can be a suitable way to move in temperatures above 10 degrees below zero, in which case it's better to do a high-impact running workout indoors. Strenuous outdoor exercise is recommended to be completely skipped when the thermometer reads -20 degrees or below.
The duration of the workout should be planned according to the temperature and the intensity of the sport. Do not vainly strive for long-lasting performance as with warm weather. The wind also has a big effect on the matter, because even at a few degrees below zero, a strong wind substantially increases the bite of the frost. The table below describes the effect of wind speed on frost bite.
| Wind speed m/s | Air temperature °C | |||||
| 0 | -5 | -10 | -15 | -20 | ||
| 2 | -3 | -8 | -14 | -20 | -26 | |
| 4 | -4 | -11 | - 17 | -23 | -29 | |
| 7 | -6 | -12 | -19 | -25 | -32 | |
| 10 | -7 | -14 | -20 | -27 | -34 | |
| 13 | -8 | -15 | - 22 | -28 | -35 | |
Dressing
When preparing for outdoor training, it is of course particularly essential to dress in layers, which everyone is familiar with. The function of the layer of clothing against the skin is to transfer moisture from sweat away from the skin, helping to keep the skin dry and warm. In the middle layer, you should prefer airy and insulating materials, such as merino wool. Choose a breathable and water-repellent material as the top layer, depending on the activity, for example a softshell or top layer. When dressing in layers, it is also easy to adjust the amount of clothes as needed. However, you should not exaggerate with layers of clothing, it is often good that it is a little cool when you go to training, because the body warms up substantially during exercise.
In cold weather, the peripheral parts of the body (hands, toes, ears) are the most sensitive to frostbite, so invest especially in good gloves, beanie, socks and shoes/overalls. Pay special attention to the face during exercise, because protecting the face is the most difficult of all, and frostbite is easily visible, for example, in pale and tingling cheeks.
Attention to breathing
The air humidity in the lungs is normally high, but in cold weather, especially during exertion, the airways dry out and cool down.
When it's cold, it's recommended to use, for example, a thin scarf or other protection in front of the nose and mouth, which helps to warm and moisten the breathing air. Some of the active winter walkers also use breathing air heaters sold in pharmacies, which bind the heat of exhalation and use it to heat the inhaled air. At the same time, the honeycomb moistens the dry and cold frosty air into a pleasant moisture for the body. However, the protection puts a small resistance on breathing, so you can't achieve the same performance with it as in warm weather.
Remember to warm up
Start the exercise calmly so that the muscles have time to warm up. In the cold, you should reserve much more time than usual for warming up. Exercisers are also recommended to do a light warm-up indoors before going outside, so that the muscles are ready for exercise faster. However, you should avoid sweating inside, as this guarantees a quick cooling down as soon as you get outside. Also go indoors immediately after training so that you don't catch a cold when you're sweating.
Change
Also remember hydration! In the cold, you don't feel the same thirst as in the warm, but that by no means means that the body doesn't need hydration. When it's cold, you should take a warm (but not hot) drink with you, so your body doesn't have to use extra energy to heat up cold water.
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