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Protection against cold: When we swim in cold water, our body becomes exposed to sudden temperature drops. Keeping our hands above the water helps to limit heat loss through the hands. The skin is sensitive to cold, so keeping it above the water helps to avoid direct contact with cold water. Facilitating breathing: It can be difficult to breathe while swimming, especially if you are submerged in cold water. Keeping your hands above the water allows for easier access to air and facilitates breathing, which is particularly important when you need to find a hole in the ice or an opening to resurface. Safety: Keeping your hands above the water can also serve as a signal for other swimmers or observers. This helps to identify people in the water and can be used as a form of communication. Relaxation: Some people enjoy keeping their hands above the water while swimming as a form of relaxation. It helps with concentration and controlling breathing while submerged in cold water.

I held it that way too while ice-swimming, not knowing why 🙂 everyone held it that way, so I did too 🙂. I'm curious to find out. 🙂 Rather, probably not to improve blood circulation in the hands, because for that, thermal stimulation is needed, hot-cold.

Probably cold, hands freezing then it's hard to dress.

They improve the circulation of their blood in this way.

Diving, or swimming in cold water, is a popular way to improve health and well-being. The reason why people who go diving hold their hands up while in the water has several functions. 1. Thermoregulation: Holding the hands above the head helps to maintain heat in the head. The head is one of the places where the body loses the most heat, so divers try to limit this loss by directing more blood to this area. During diving, holding the hands above the head helps to maintain heat in this area of the body. The head is one of the places where the body loses the most heat, so divers try to limit this loss. 2. Lowering the risk of frostbite: Holding the hands above the head increases blood flow to the upper limbs, which can help prevent frostbite. The increased blood reaching the hands helps keep them warm, minimizing the risk of frostbite or freezing of the fingers. Holding the hands above the head increases blood flow to the upper limbs, which helps prevent frostbite. Keeping the hands warm reduces the risk of frostbite or freezing of the fingers. 3. Strengthening the therapeutic effect: Diving has a beneficial impact on the immune system and overall body condition. Holding the hands up can additionally enhance therapeutic effects by influencing blood circulation, endorphin secretion, and stress reduction. Holding the hands up during diving can additionally enhance therapeutic effects such as improving blood circulation, endorphin secretion, and reducing stress. In summary, divers hold their hands up to regulate body temperature, prevent frostbite, and strengthen therapeutic effects. This is one of the practices that help enjoy the health benefits of diving in cold water.