Cross-country skier on treadmill (IMAGE) Norwegian University of Science and Technology Caption Thirteen top cross-country skiing athletes participated in the study and used the large treadmill at NTNU. Photo: Trine M. Seeberg Credit Trine Margrethe Seeberg Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. Adaptations must be shared under the same terms. License CC BY-NC-SA Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.