Cross‐Country Skiing

Abstract

The purpose was to study the adaptation to speed in the temporal patterns of the movement cycle and determine any differences in velocity, cycle rate and cycle length at the maximum speed level in the different classical style and freestyle cross-country skiing techniques. Eight skilled male cross-country skiers were filmed with a digital video camera in the sagittal plane while skiing on a flat cross-country ski track. The skiers performed three classical style techniques the diagonal stride, kick double poling and the double poling technique and four freestyle techniques paddle dance (gear 2), double dance (gear 3), single dance (gear 4) and combiskate (gear 5) at four different self-selected speed levels slow, medium, fast and their maximum. Cycle duration, cycle rate, cycle length, and relative and absolute cycle phase duration of the different techniques at the different speed levels were analysed by means of a video analysis system. The cycle rate in all tested classical and freestyle techniques was found to increase significantly (p < .01) with speed from slow to maximum. Simultaneously, there was a significant decrease in the absolute phase durations of all the investigated skiing techniques. A minor, not significant, change in cycle length, and the significant increase in cycle rate with speed showed that the classical and freestyle cross-country skiing styles are dependent, to a large extent, on an increase in cycle rate for speed adaptation. A striking finding was the constant relative phase duration with speed, which indicates a simplified neural control of the speed adaptation in both cross-country skiing styles. For the practitioner, the knowledge about the importance of increasing cycle frequency rather than cycle length in the speed adaptation can be used to optimise a rapid increase in speed. The knowledge about the decrease in absolute phase duration, especially the thrust phase duration, points to the need for strength and technique training to enable force production at a high cycle rate and skiing speed. The knowledge that the relative phase duration stays constant with speed may be used to simplify the learning of the different cross-country skiing techniques.

Numerical optimization of pacing strategy in cross-country skiing

“…The assumption that mechanical efficiency decreases rapidly at a of 10 m/s can be supported by d-GNSS data presented by Andersson et al (2010), which shows at which speed every "gear" (Nilsson et al 2004) is performed. Judging by the deviation of gear speed in Andersson et al (2010), in (3) might be treated as an individual parameter, one that is probably affected by the size of the athlete as well as his rapidness and technical skills.…”

Identification of Cross-Country Skiing Movement Patterns Using Micro-Sensors

“…The following cross-country skiing techniques were chosen for analysis: Skating techniques: (classified as gears G2-G5 according to Nilsson et al [1]) Offset Skate (G2)Double Time (G3)Single Time (G4)Free Skate (G5)Classical techniques: (universally used definitions) Double Pole (DP)Kick Double Pole (KDP)Diagonal Stride (DS)…”

“…Skating techniques: (classified as gears G2-G5 according to Nilsson et al [1]) Offset Skate (G2)Double Time (G3)Single Time (G4)Free Skate (G5)…”

“…No other sport has such a wide range of repetitive movement patterns used in one event. There are two main event styles, skating and classical, each of which has four main sub-techniques or “gears” used in competition [1]. Efficient selection of an appropriate gear depends on the gradient of the terrain and the velocity at which a skier is travelling [2].…”

A simulation of cross-country skiing on varying terrain by using a mathematical power balance model

“…Explicit dependencies of metabolic rate Q on the friction coefficient, body mass, air drag, and cycle length were not assumed. In principle, cycle rate and technique vary with angle of inclination and speed 21,22. However, we assume that an individual skier will voluntarily prefer the most economical cycle rate for a chosen technique.…”