Running at freezing temperatures?

The lungs protect themselves against the cold

The lungs’ protective mechanism against the cold is based on the Hagen-Poiseuille law which describes the dependence between flow velocity and vessel radius. Beginning from the trachea, the bronchial system divides into smaller and smaller branches ending in the alveoli, in which the gas exchange takes place. When we breathe in cold air, the diameter of the bronchial pathways decreases steadily. In congruence with the Hagen-Poiseuille law, the flow resistance increases while the flow velocity of the inhaled air is reduced. This way, the inhaled air stays in contact with the bronchial arteries longer, warming the air on its way to the alveoli. Breathing through the nose can further this process, as the air has to cover a longer distance until it reaches the lungs. For healthy people, running at lower temperatures is not an issue. The immune system benefits from regular running sessions, although this is mainly due to the physical activity rather than the cold temperatures themselves. Asthmatics and those with chronic pneumopathy should, however, exercise with caution in very cold, dry air. 

Wearing the right clothes

When running in lower temperatures, it’s important to be prepared, particularly when it comes to your choice of sportswear. Most sportswear manufacturers have already adapted their range for those running during winter, offering functional sportswear made from breathable fabrics, that absorb sweat away from the body to keep you cool. Feeling slightly cold at the beginning of your run is perfectly normal. After only a few minutes, your body temperature will rise and you will no longer feel the cold. Many runners tend to make the mistake of dressing too warm in winter, which puts a strain on circulation. Training in sweaty clothes also increases the risk of infection.

In cold and damp weather, the multi-layer principle has proven to be the most effective, consisting of functional underwear, a thermal-insulating running shirt and a wind/waterproof jacket. Gloves and a beanie are indispensable items when jogging in winter, as heat is lost through the head and hands, so without a protective layer they will cool down quickly. If the ground is covered in ice and snow, please take care in choosing your footwear accordingly to prevent injury. With falling darkness, reflective clothing also provides more visibility and security.

Less is more, at least in Winter

When running in Winter, it’s advisable to start out slow with warm-up exercises, proper stretching and controlled breathing. Because of the poor blood supply to the muscles and slowed defensive reflexes, the risk of injury is higher than during warmer temperatures. Joggers should therefore not expect their best performances in Winter and rather adapt their pace to the weather and ground conditions. After the workout, it’s important to get out of any damp clothes as soon as possible, followed by a hot shower. Afterwards, be sure to stay hydrated. By following these steps, nothing can stop you from exercising, even during Winter. Your body benefits from the fresh air and movement, while your soul is rewarded with the satisfying knowledge that you did something for yourself. But should the temperatures drop further and your preferred running course is covered in ice, it’s best to switch to the treadmill instead.

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