Ljubljana Glacier: physical activity

Our bodies have mechanisms to adapt to higher temperatures over time. When exposed to heat, the body's response, such as sweating, becomes faster, increasing sweat volume, lowering body temperature and reducing electrolyte concentration. Increased blood flow to the skin is crucial for dissipating excess heat. However, these adaptations take time to develop. Therefore, it's important, especially at the start of summer or during the first heat wave, to take precautions to minimise heat stress (1).

If we anticipate exposure to heat, there are ways to partly mitigate its effects. Moderate exposure to heat, like one hour of physical activity during moderate temperatures each day, a few days before the heat wave, can help with adaptation. It's essential to stay hydrated and replace electrolytes. Additionally, visiting a sauna not only aids heat adaptation but also offers other health benefits (1).

During a heat wave, the development of health issues is influenced by both heat and humidity. When the environment is hotter than our body temperature, the only cooling mechanism is through evaporation—water evaporating from the skin's surface. If the air is humid, this process becomes less effective, making us more vulnerable to heat stress. Rising core body temperature, combined with physical activity generating internal heat, can lead to heat stroke (2). 

For safe recreational activities during heat waves, remember to: 

  • Choose appropriate timing and location, opting for early mornings or evenings and avoiding sun-exposed urban areas.
  • Wear lightweight, breathable, light-coloured clothing and a hat
  • Stay hydrated by replenishing electrolytes.
  • Cool down through activities like taking cold showers or swimming in a lake or sea.
  • If experiencing signs of heat exhaustion (fatigue, muscle cramps, dizziness, etc.), immediately stop physical activity, find shade in a cool area, and ensure adequate hydration.


The Ljubljanski ledenik (Ljubljana Glacier) project is an initiative dedicated to raising awareness about the significance, impact, and protection against heat waves. Discover more valuable content on posters strategically placed throughout the city centre and by visiting the following link. The project is co-funded by the Municipality of Ljubljana.

(1) Périard, J.D., Racinais, S. and Sawka, M.N. (2015), Adaptations and mechanisms of heat acclimation. Scand J Med Sci Sports, 25: 20-38. URL: https://doi.org/10.1111/sms.12408
(2) Patološka fiziologija; učbenik za študente farmacije: druga, popravljena izdaja (2019), Ljubljana, Medicinska fakulteta, Inštitut za patološko fiziologijo