S.S. Dubrovinskiy
PhD, Professor A.G. Batalov
V.G. Senatskaya
Russian State University of Physical Culture, Sport, Youth and Tourism (GTSOLIFK), Moscow

Keywords: techniques, tactics, modelling, cross-country ski race, technical and tactical mastery.

Background. In modern cross-country ski races, athletic performance standards are so close that have virtually achieved their natural limits. It is not unusual for the modern ski sport that winners of major sprint events are determined by photo-finish systems, and this is indicative of generally the same levels of physical and functional fitness of many contenders for the awards. In the situation of such a high “density” of the athletic performance standards, it is the individual technical and tactical mastery that comes to the forefront as a key for success.

Objective of the study was to find model specifications for successful technical and tactical competitive techniques applied in elite cross-country ski sprints.

Methods and structure of the study. In the technical and tactical skills and techniques identification and modelling process, we analyzed the competitive success records of 24 elite cross-country (men and women) skiers who competed in finals of the 2013 Nordic World Ski Championship in Val di Fiemme and 2015 Nordic World Ski Championship in Falun. We processed 16 race protocols of competitions, 96 individual competitive records and 4-hour video captures. Having analyzed the race protocols, we obtained average distance speeds of the finalists and the speed variation data for the final events. Kinematic individual performance characteristics of the ski sprinters were received by video data analyses and the race timing studies. It should be noted that the individual sprint events in the 2013/ 2015 Nordic World Ski Championship finals were run in classical style. Furthermore, the study data included the competition track configuration studies, with the tracks being broken down for the purposes of the study into starting, racing and finishing sections.

Study results and discussion. The finalists’ race speed data and data variation analyses demonstrated that the female ski sprinters showed the slowest results in the qualifying races of the 2013 NWSC (5.79±0.019 m/s) and the quarter-final races of the 2015 NWSC (6.65±0.007 m/s). Male skiers were the slowest in the final race of the 2013 NWSC (6.92±0.50 m/s) and the semi-final race of the 2015 NWSC (7.60±0.019 m/s).

The women’s fastest event in the 2013 NWSC was the final race (5.99±0.023 m/s), and the fastest men’s event was the semi-final race (7.11±0.001 m/s). In the 2015 NWSC, both women and men were the fastest in the qualifying race (6.80±0.005 m/s and 7.69±0.060 m/s, respectively).

Having analyzed the key technical and tactical performance indicators of the finalists, we found that the women’s average movement cycle frequency rate was the same throughout every race staying at 1.30±0.030 c/s [cycles per second] in the 2013 NWSC and 1.27±0.026 c/s in the 2015 NWSC; whilst the male finalists achieved the maximum movement frequency rates in the final races: 1.27±0.01 c/s at the 2013 NWSC and 1.30±0.004 c/s at the 2015 NWSC.

Average men’s skiing style changeovers were estimated at 13-14 in the 2013 NWSC and 12-14 in the 2015 NWSC; and the women’s changeovers at 13-16 in the 2013 NWSC and 12-14 in the 2015 NWSC.

Furthermore, we identified individual model specifications of the competitive performance profiles of the 2013/ 2015 NWSC winners (see Table 1 hereunder).

Table 1. Technical and tactical competitive performance profiling data of the 2013/ 2015 Nordic World Ski Championship winners

Marit Bjorgen, winner of the 2013 Nordic World Ski Championship, opted for the race lead tactics in every event except for the final race; and in the final race she changed over to the leader pursuit tactics, and it was only on the final climb that she spurted forward. Her highest ski stride changeover count of 15 was fixed in the final race. Her race speed in the final was estimated at 6.10 m/s; movement cycle frequency rate in the finishing section of the distance was 1.25 c/s (i.e. 75 pole kicks per minute) in the double-pole technique.

On her way to success in the 2015 Nordic World Ski Championship, Marit Bjorgen opted for the leader pursuit tactics in every event, with her ski stride changeovers making up 14 in every race; her racing speed in the final race metered at 6.77 m/s; and the movement cycle frequency rate in the finishing section making up 1.25 c/s (i.e. 75 pole kicks per minute) in the double-pole technique.

Nikita Kriukov, winner of the 2013 Nordic World Ski Championship, preferred the leader pursuit tactics in every event, with his ski stride changeovers coming to 14 in every race; his racing speed in the final was 7.12 m/s; and the movement cycle frequency rate in the finishing section estimated at 1.47 c/s (i.e. 88.2 pole kicks per minute) in the double-pole technique.
Petter Northug, winner of the 2015 Nordic World Ski Championship, opted for the leader pursuit tactics in every event; but in the final race he made a sudden spurt on the very first climb and came to the lead. He made only 12 ski stride changeovers in every race, the lowest count in the group of finalists. His racing speed in the final was 7.67 m/s, and the movement frequency rate in the finishing section was 1.38 c/s (i.e. 82.8 pole kicks per minute) in the double-pole technique.

Having analyzed the technical and tactical performance profiling data of the 2013/ 2015 Nordic World Ski Championship winners, we arrived to the following three frame competitive performance models:

Model 1 (women) implies a race lead tactics from the start to the finish as was the choice of Marit Bjorgen, winner of the 2013 Nordic World Ski Championship. Given in Figure 1 is her competitive performance profiling data with the following things to be noted: the racing speed grew with every event and came to its maximum in the final race; the ski stride changeovers were kept within the range of 14-16 per distance; the movement cycle frequency in the finishing section was estimated at 1.25 c/s, with the average frequency of all the races making up 1.34 c/s.

Figure 1. Racing speed profile of the 2013 Nordic World Ski Championship winner (women final)

Model 2 (women) is based on the leader pursuit tactics that was opted for by Marit Bjorgen in the 2015 Nordic World Ski Championship. As seen on Figure 2, she showed the lowest racing speed in the quarter-final and the maximum speed in the final – as it was the case in the 2103 NWSC. Her ski stride changeovers were the same (14) in every race; the movement cycle frequency in the finishing section was estimated at 1.25 c/s, with the average frequency of all the races making up 1.22 c/s.

Figure 2. Racing speed profile of the 2015 Nordic World Ski Championship winner (women final)

Model 3 (men) implies the leader pursuit tactics. Given on Figure 3 are the competitive performance profiles that show both men finals winners being the slowest and fastest at the start of the events. Their ski stride changeovers varied within 12-14 per distance; the movement cycle frequency in the finishing section was estimated at 1.42 c/s, with the average frequency of all the races making up 1.25 c/s.

Figure 3: Racing speed profile of the 2013/ 2015 Nordic World Ski Championship winners (men finals)

Conclusion. The competitive performance model specifications offered herein may be beneficial when planning and implementing elite ski racers’ training programs to prepare them for the major international cross-country ski competitions.

References

1. Batalov A.G. Model'no-tselevoy sposob postroeniya sportivnoy podgotovki vysokokvalifitsirovannykh sportsmenov v zimnikh tsiklicheskikh vidakh sporta (stat'ya vtoraya) (Model-target method of organization of training of elite athletes in winter cyclic sports (Article Two) / A.G. Batalov // Teoriya i praktika fizicheskoy kultury. – 2001. – № 2. – P. 8–13.
2. Ramenskaya T.I. Taktika lyzhnikov-olimpiytsev v sorevnovatel'nykh distsiplinakh novogo stoletiya (Tactics of Olympic skiers in competitive disciplines of the new century) /T.I. Ramenskaya, K.M. Geraskin // Olympic Bulletin / [comp.: N.Yu. Melnikova [et al.] ; Centre of Olympic. Acad., Rus. State. Univ. Phys. Culture, Sport, Youth and Tourism (GTSOLIFK). – Moscow, 2011. – № 12. – P. 150–160.
3. Sidelev P.A., Batalov A.G. Osobennosti sorevnovatel'noy deyatel'nosti i faktory, opredelyayushchie dostizhenie vysokogo rezul'tata v lyzhnom sprinte (Specificity of competitive activity and factors to determine success in ski race) / P.A. Sidelev, A.G. Batalov // Mater. Vseros. nauch.-prakt. konf. «Aktual'nye voprosy podgotovki lyzhnikov-gonshchikov vysokoy kvalifikatsii» (Proc. res.-pract. conf. "Actual issues of training of elite racing skiers". - Smolensk, 2012. – P. 144–148.

Corresponding author: Oxbow2004@mail.ru

Abstract
The article studies the technical and technical performance profiles of elite cross-country skiers, both male and female, in the individual sprint finals of the 2013/ 2015 Nordic World Ski Championships (NWSC). The key performance criteria to rate the competitive success in the qualifying and final sprint events (including the qualifying, quarter-final, semi-final and final races) were the following: racing speed, movement frequency, ski stride changeovers on distance and the winners’ individual tactics in the final races. Having analyzed the study data, we found generalized (frame) and individual model specifications of the elite cross-country skiers’ technical and tactical performance in the highly competitive ski sprint events. The competitive performance model specifications offered herein may be beneficial for those who organize elite ski racers’ training programs and coaches in training for the major international cross-country ski competitions.