In alpine skiing, athletes are faced with a variety of environmental conditions. For example, during the summer preparation phase, this includes glacier training at altitudes of over 3,000 metres. However, training at altitude can lead to metabolic changes such as increased energy turnover and loss of appetite, as well as an elevated risk of experiencing an energy deficit.
The Professorship of Exercise, Nutrition and Health headed by Prof. Dr. Karsten Köhler has started a new research project based on these assumptions. EBal-Ski” (“Energy Balance in Alpine Skiing taking Altitude into Account”) is a new project intending to characterise the energy balance of international ski racers during training at altitude as well as over the course of the season using tried and tested measuring methods. The service research project in cooperation with the German Ski Association (DSV) will run for nine months and is funded by the Federal Institute for Sports Science with a budget of €35,000. “The project is part of a broader research direction,” explains Prof. Köhler. “We have been dealing with the question of how an athlete's energy metabolism develops in extreme situations for years.”
The study has two main objectives: Firstly, it will investigate how altitude affects energy balance during a five to ten-day training camp. Here, the focus lies with the analysis of the total energy turnover, recording the total energy supply, changes in body composition and analysing the energy metabolism's key blood markers. Secondly, physical changes over the course of the season will be monitored, taking the altitude profile into account. “This involves comparing body composition before and after the competition season,” explains Helena Engel, nutritionist and doctoral candidate at the Professorship of Exercise, Nutrition and Health. Furthermore, comprehensive documentation regarding body weight over the course of the season as an indicator to determine energy balance will also be compiled. “Skiers are subject to extremely high energy requirements,” says Prof. Köhler, describing the conditions. “However, this also entails the risk that they will lose weight unintentionally during the season resulting in negative effects in terms of performance”.
The participants are five to eight male and female members of the German Alpine Ski Team between the ages of 18 and 35. Due to the relatively small group of participants who are all competing in high-performance sports, Engel's research team is hoping to obtain highly reliable measurement results, “moreover, we can respond to each athlete individually. The research period runs from pre-season preparations to the end of the competition season. Measurements will be taken at four points in time: at the beginning of the season, before and after the altitude training camp and at the end of the season.
Several methods will be implemented during the study in accordance with the respective gold standards. At the altitude training camp, the athletes' energy consumption is measured using doubly-labelled water. “A small amount of water marked with stable water and oxygen isotopes is administered for tracking,” says Helena Engel. “Afterwards, we will measure how these isotopes accumulate in the urine of the test subjects.”
In order to obtain information about the energy balance, the athletes' energy intake is also recorded. For this purpose, an objective computational approach will be applied in addition to the direct recording of food intake. Changes in body composition will be studied using the “four-compartment model”, which considers the body's chemical components. The resting metabolic rate can be determined using indirect calorimetry, a method for measuring an organism's or chemical reaction's energy metabolism. Furthermore, daily weight data will be independently collected from the study participants via the use of standardised Bluetooth scales in compliance with a specified weighing protocol.
“In my opinion, this is an important project for practical applications with the aim of obtaining reference values for skiers' energy consumption. So far, there is very little data that can be used in this field, especially with regard to alpine skiing,” Engel concludes.
To the homepage of the Professorship of Exercise, Nutrition and Health
To the homepage of the German Ski Association (DSV)
Contact:
Prof. Dr. Karsten Köhler
Professorship of Exercise, Nutrition and Health
Georg-Brauchle-Ring 60/62
80992 München
phone: 089 289 24488
e-mail: karsten.koehler(at)tum.de
Helena Engel
Professorship of Exercise, Nutrition and Health
Georg-Brauchle-Ring 60/62
80992 München
phone: 089 289 24441
e-mail: helena.engel(at)mri.tum.de
Text: Romy Schwaiger
Photos: Pixabay/private