Differences in pacing pattern and sub-technique selection between young and adult competitive cross-country skiers.

Abstract

The present study describes differences in pacing patterns and sub-technique selection in young compared to adult competitive cross-country skiers. Eleven young male skiers (YOS) (14.4±0.5years, O2peak 63.9±2.8mL∙kg-1 ∙min-1 ) and eight adult male skiers (ADS) (22.6±4.3years, O2peak 77.4±4.4mL∙kg-1 ∙min-1 ) performed a free technique rollerski time trial (TT) over a distance of 4.3km (YOS) and 13.1km (ADS) to simulate normal racing distances. A GNSS/IMU system was used to track position, speed, and classify sub-techniques. Skiing economy and O2peak were measured on an additional day to calculate the relative oxygen demand ( O2dem ) in 13 segments of the TT. YOS were slower than ADS in all types of terrain (mean speed difference of 13%), with differences for uphills of 19%, undulating terrain of 11% and downhills of 8% (all P<.05). The mean relative O2dem tended to be higher for YOS compared to ADS (120% vs 112% of O2peak , P=.09), and the difference was more pronounced in the initial four segments of the race (130% vs 110% of O2peak , P<.01). YOS used more of the sub-technique Gear 2 (23±7 vs 14±4%), less Gear 3 (36±7 vs 45±5%), and had more frequent transitions between sub-techniques (18±2 vs 15±3km-1 ) (all P<.05) than ADS. Over an age-related distance, young skiers tend to exhibit higher mean exercise intensity than adult elite skiers, with a more pronounced positive pacing pattern. Differences in physical ability affect speed and sub-technique selections, implying a need for differentiating technical training for different ages and levels.