The Interval-Based Physiological and Mechanical Demands of Cross-Country Ski Training

To investigate fluctuations in speed, work rate and heart rate (HR) when cross-country (XC) ski skating across varying terrain at different endurance training intensities. Seven male Norwegian junior skiers performed maximal speed (V ) tests in both flat and uphill terrain. Thereafter, 5-km sessions at low- (LIT), moderate- (MIT), and high-intensity (HIT) were performed based on their own perception of intensity, while monitored by a global navigation satellite system (GNSS) with integrated barometry and accompanying HR monitor. Speed, HR and rating of perceived exertion gradually increased from LIT to MIT and HIT, both for the total course and in flat and uphill terrains (all P