Feeling Unwell During the Rainy Season? It Might Be Rainy-Season Heatstroke

梅雨の「なんとなく不調」は気のせいじゃない!「梅雨型熱中症」にご用心 - C-one ONLINE STORE

When the rainy season begins, do you ever feel unusually sluggish, find it hard to stay focused, or struggle to get out of bed in the morning? These vague, hard-to-explain discomforts may seem minor because the weather is not as hot as midsummer. However, there may be a hidden risk of “rainy-season heatstroke” during this time of year. If you lead an active lifestyle, this is something worth checking carefully.

It’s Not Just About Temperature: Why Rainy-Season Heatstroke Can Sneak Up on You

When people hear the word “heatstroke,” many imagine the blazing sun of midsummer. However, rainy-season heatstroke is closely related to the cool yet highly humid climate that is typical of the rainy season.

Why does the risk of heatstroke increase during the rainy season? There are three main reasons.

  • High humidity makes it difficult for sweat to evaporate: Sweat plays an important role in lowering body temperature. However, when humidity is high, sweat does not dry easily. As a result, heat can remain trapped in the body, making it easier for body temperature to rise.
  • The body is not yet used to the heat: Since the rainy season comes before the peak of summer, the body may not be fully prepared for hot weather. Sudden changes in temperature and humidity can make it difficult for the body’s temperature-regulating system to keep up.
  • Imbalance in the autonomic nervous system: During the rainy season, atmospheric pressure often fluctuates, and daylight hours may be shorter. These changes can disturb the balance of the autonomic nervous system, making it harder for the body to regulate temperature properly.

Without realizing it, your body may be under stress from the seasonal changes unique to this time of year.

Do Any of These Symptoms Sound Familiar?

The symptoms of rainy-season heatstroke are very similar to ordinary heatstroke. However, because many people assume, “Surely not at this time of year,” it can often go unnoticed.

  • General fatigue or sluggishness
  • Headaches or dizziness
  • Loss of appetite or mild nausea
  • Numbness in the hands or feet, or muscle cramps
  • Difficulty concentrating or feeling physically unrefreshed

If several of these symptoms apply to you, they may be signs of rainy-season heatstroke.


How to Stay Comfortable During the Rainy Season: Simple Steps You Can Start Today

To stay active and comfortable every day, it is important to take early measures against rainy-season heatstroke.

  1. Create a comfortable space by controlling humidity
    Use the dry mode on your air conditioner or a dehumidifier to lower indoor humidity. Opening windows for ventilation and circulating air with a fan or circulator can also be effective.
  2. Make conscious hydration a habit
    Even when you do not feel thirsty, your body is constantly losing water. Try to drink fluids regularly at set times, such as after waking up, before and after exercise, before and after bathing, and before going to bed. In addition to water and tea, sports drinks or oral rehydration solutions can also be useful for replenishing salt lost through sweat.
  3. Build heat tolerance gradually
    As summer approaches, it is important to gradually help your body adapt to the heat. Light activities such as walking, gentle jogging, or stretching can help you work up a mild sweat without overexertion. Taking a slow bath in lukewarm water is also recommended.
  4. Let comfortable clothing support your body
    Clothing that sticks to the skin after sweating can be uncomfortable and may also interfere with body temperature regulation. This is where C-one’s 100% Merino wool T-shirts can be a reliable choice. Although Merino wool is a natural material, it has excellent moisture absorption and release properties, helping absorb sweat quickly and release it efficiently from the fabric surface. As a result, it helps keep the skin dry and comfortable, while also reducing the chill that can come from sweat. In addition, its odor-resistant properties help reduce concerns about sweat odor, supporting active days with greater comfort. Its gentle natural texture against the skin is another reason it can be worn comfortably without stress.
  5. Recover with quality sleep and balanced nutrition
    To refresh both body and mind, make sure to get enough sleep and maintain a balanced diet. During the rainy season, the body can easily feel heavy and sluggish, so it is helpful to consciously take in vitamins and minerals.

If You Feel Unwell, Take Action Early

If you experience symptoms that make you think, “Could this be rainy-season heatstroke?” avoid pushing yourself. Move to a cool place and cool your body, especially around the neck, underarms, and groin area. Do not forget to replenish fluids and salt. If your symptoms do not improve, or if you feel that something is different from usual, please seek medical attention without hesitation.

Even during the humid and uncomfortable rainy season, you can stay active and healthy by using the right knowledge and comfortable items such as C-one’s Merino wool T-shirts.


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