Prepared for the mountains?

Easter is here – have you tested your equipment and brought enough food for your trip to the mountains?

Testing oxygen consumption during moderate and intense digging in the snow.

Resting energy consumption increases in the cold climate. When working outdoors in the cold, factors such as temperature, wind chill, food and water intake, clothes and gear for protection need to be considered. Preparing in advance in case of stormy weather is essential for outdoor activities like breaking camp, or digging snow shelters. It is critical to bring the necessary equipment if you plan to, or by accident need to spend one or more nights outdoors.

Not only is equipment such as tent, storm shelter bag, sleeping bag and padding, shuffle, snow saw and cooking equipment necessary, you also need to check the quality and workability of your gear beforehand. Raise and dismantle your tent at home, check the status of your sleeping bag and “test-burn” your primus! These are some of the equipment tests for preparing for your mountain trip.

Making an emergency shelter, such as a snow cave, by digging and sawing snow and moving blocks of snow is both time consuming, and requires great energy consumption. During the “Enjoy the Cold” physiology class at Ny Ålesund, Svalbard, maximal oxygen consumption and oxygen consumption during snow sawing and digging was measured in participants.  In one participant with a maximal oxygen consumption of 49.5 ml∙kg-1∙min-1 (3.65 L∙min-1) the oxygen consumption during snow sawing and digging were at a steady state value of 32 ml∙kg-1∙min-1 (2.35 L∙min-1) while maximal values during intense digging was a high as 42 ml∙kg-1∙min-1 corresponding to 65% and 85% of maximal oxygen consumption (see the picture above).

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Cold physiology: What to do in case of hypothermia?

Two CERG post doctors, Trine Karlsen and Svein Erik Gaustad are spending this week at the enjoy the cold physiology class in Ny-Ålesund, Spitsbergen, a research station run by the Kings Bay company at 79 degrees north. The class is organized by the hyperbaric research group at Department of Circulation and Medical Imaging at NTNU, with participants from the Norwegian and Swedish armies, Norwegian petroleum companies and departments, the University of Tromsø and NTNU. The class is a mixture of theoretical and practical training in how to plan and behave when exposed to the artic climate. For the oil and shipping industry this is vital knowledge for the coming artic expansion.

Hypothermia and circulation
A person is hypothermic when core temperature drops below 35 degrees Celsius. At this temperature the body is unable to increase body temperature by self-produced heat when remaining in the cold environment. At core temperatures of 28 degrees, severe hypothermia is present and is associated with unconsciousness and cardiac arrhythmias.  Individuals may reach exhaustion already at mild to moderate hypothermia due to increased bodily stress.

The respiratory rate increases significantly, and heart rate may be close to maximum early during core cooling.  When core temperature continues to decrease to 25°C degrees, heart rate decreases dramatically to values as low as 25 beats per minutes. At this point the risk of ventricular fibrillation and cardiac arrest increases dramatically, and must be accounted for when transporting and treating severely hypothermic individuals.

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5. des: Høydetrening – Hvor høyt, hvor lenge og hvor effektivt i utholdenhetsidretter?

Akutt eksponering til høyde = redusert utholdenhetsprestasjon
Høydetrening gjennomføres ofte mellom 1500-2500 meters høyde. På grunn av redusert oksygentrykk vil kondisjon (som målt ved maksimalt oksygenopptak) reduseres med ca 6-10 % per 1000 meters økning i høyde over havet fordi det er mindre oksygen tilgjengelig for arbeidende muskulatur. Dette betyr at kvaliteten på trening som gjennomføres i høyden er redusert i starten av et høydeopphold. Maksimal fart vil være redusert i utholdenhetsidretter, og både hjertefrekvens og melkesyre vil være høyere på samme hastighet i høyden sammenlignet med i lavlandet.

Idrettsutøvere med svært god kondisjon får en større reduksjon i kondisjon mellom 1500-4500 meters høyde sammenlignet med utrente personer, og opplever redusert kondisjon allerede på 650 meter over havet. Det betyr at utrene og moderat trente personer blir mindre påvirket når de skal trene og prestere i høyden. Det er fortsatt uklart hvorfor godt trente idrettsutøvere er mer sårbar i høyden, men det antas at det henger sammen med et stort hjerte som pumper større mengder blod under maksimal aktivitet. Med tanke på den negative effekten opphold i høyden har på treningskvalitet, hvorfor er høydetrening så populært blant idrettsutøvere?

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Let your dog talk you into exercise!

According to a study published in the Journal of Physical Activity and Health, people owning dogs are more physically active than non-dog owners. Being a dog owner was associated with more walking and leisure time activity compared to in non-dog owners. The odds for obtaining at least 150 minutes per week of total walking were 34% higher for dog owners compared to non-dog owners, with higher levels of moderate and vigorous activity. In a study of older subjects (70-80 years old), dog-owners were more likely to do regular walking if they had a dog companion rather than a human. Despite increased leisure time activity in dog-owners, a great portion of dog-owners do not walk or exercise with their dog. If you are a dog owner, forget about bad weather and let your dog “talk you into” daily outdoor exercise.

Written by Trine Karlsen, Post Doctor at CERG.