Publications
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Magelssen, Christian; Haugen, Per; Reid, Robert Cortas & Gilgien, Matthias
(2022).
Is there a contextual interference effect for sub-elite alpine ski racers learning complex skills?
Frontiers in Bioengineering and Biotechnology.
ISSN 2296-4185.
10.
doi:
10.3389/fbioe.2022.966041.
Show summary
Scientific understanding of the contextual interference effect stems mainly from studies on unskilled participants learning artificial laboratory tasks. Although one goal of such studies is to extrapolate the findings to include real-world learning situations such as sports, this generalization is not straightforward. This study tested the contextual interference effect with 66 sub-elite, competitive alpine ski racers who learned a new movement pattern−the pumping technique to increase velocity in slalom−by practicing this skill in three different slalom courses over a 3-day training period. The interleaved group practiced all three courses each day in a semi-random order. In contrast, the blocked group practiced only one course each day, which was randomized and counterbalanced across the participants in this group. A retention test was delivered 72 h after the last practice day. In contrast to our hypothesis, the interleaved group did not display significantly better retention than the blocked group. The interleaved group’s performance was also not significantly attenuated during skill learning compared to the blocked group. Our results underscore the importance of conducting motor learning experiments in natural environments to understand the conditions that facilitate learning beyond the laboratory environment.
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Elfmark, Ola; Ettema, Gertjan; Groos, Daniel; Ihlen, Espen Alexander F.; Velta, Rune & Haugen, Per
[Show all 8 contributors for this article]
(2021).
Performance analysis in ski jumping with a differential global navigation satellite system and video-based pose estimation.
Sensors.
ISSN 1424-8220.
21(16).
doi:
10.3390/s21165318.
Full text in Research Archive
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This study investigated the explanatory power of a sensor fusion of two complementary methods to explain performance and its underlying mechanisms in ski jumping. A differential Global Navigation Satellite System (dGNSS) and a markerless video-based pose estimation system (PosEst) were used to measure the kinematics and kinetics from the start of the in-run to the landing. The study had two aims; firstly, the agreement between the two methods was assessed using 16 jumps by athletes of national level from 5 m before the take-off to 20 m after, where the methods had spatial overlap. The comparison revealed a good agreement from 5 m after the take-off, within the uncertainty of the dGNSS (±0.05m). The second part of the study served as a proof of concept of the sensor fusion application, by showcasing the type of performance analysis the systems allows. Two ski jumps by the same ski jumper, with comparable external conditions, were chosen for the case study. The dGNSS was used to analyse the in-run and flight phase, while the PosEst system was used to analyse the take-off and the early flight phase. The proof-of-concept study showed that the methods are suitable to track the kinematic and kinetic characteristics that determine performance in ski jumping and their usability in both research and practice.
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Reid, Robert Cortas; Haugen, Per; Gilgien, Matthias; Kipp, Ronald & Smith, Gerald
(2020).
Alpine Ski Motion Characteristics in Slalom.
Frontiers in Sports and Active Living.
ISSN 2624-9367.
2.
doi:
10.3389/fspor.2020.00025.
Full text in Research Archive
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Important insight into ski function, and ultimately skier technique and tactics, can be gained by studying how measured ski trajectories compare to predictions based on theoretical models of ski-snow interaction mechanics. The aim of this investigation was to use a 3D kinematic data set collected on highly-skilled skiers during slalom race simulations to quantify ski motion characteristics and to compare these measures with theoretical predictions based primarily on ski geometrical characteristics. For slalom turns on moderate steepness (19°), ski edging angles reached maximum values of 65.7 ± 1.7° and 71.0 ± 1.9° for 10 and 13 m gate spacings. Turn radii reached minimum values of 3.96 ± 0.23 and 4.94 ± 0.59 m for the 10 and 13 m courses. These values were in good agreement with theoretical predictions by Howe (2001) of turn radius based on edging angle. Other results of the study support recent developments in understanding of the role which the ski shovel plays in groove formation during carving, and also point to the need for further study of how ski geometrical and physical characteristics interact to determine the ski's trajectory, particularly at low edge angles. These results have important implications for understanding the consequences that ski design can have for skier technique and tactics in competitive slalom skiing.
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Federolf, Peter; Reid, Robert; Gilgien, Matthias; Haugen, Per & Smith, Gerald
(2014).
The application of principal component analysis to quantify technique in sports.
Scandinavian Journal of Medicine & Science in Sports.
ISSN 0905-7188.
24(3),
p. 491–499.
doi:
10.1111/j.1600-0838.2012.01455.x.
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Analyzing an athlete's “technique,” sport scientists often focus on preselected variables that quantify important aspects of movement. In contrast, coaches and practitioners typically describe movements in terms of basic postures and movement components using subjective and qualitative features. A challenge for sport scientists is finding an appropriate quantitative methodology that incorporates the holistic perspective of human observers. Using alpine ski racing as an example, this study explores principal component analysis (PCA) as a mathematical method to decompose a complex movement pattern into its main movement components. Ski racing movements were recorded by determining the three-dimensional coordinates of 26 points on each skier which were subsequently interpreted as a 78-dimensional posture vector at each time point. PCA was then used to determine the mean posture and principal movements (PMk) carried out by the athletes. The first four PMk contained 95.5 ± 0.5% of the variance in the posture vectors which quantified changes in body inclination, vertical or fore-aft movement of the trunk, and distance between skis. In summary, calculating PMk offered a data-driven, quantitative, and objective method of analyzing human movement that is similar to how human observers such as coaches or ski instructors would describe the movement.
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Bere, Tone Tufte; Flørenes, Tonje Wåle; Krosshaug, Tron; Haugen, Per; Svandal, Inger & Nordsletten, Lars
[Show all 7 contributors for this article]
(2014).
A systematic video analysis of 69 injury cases in World Cup alpine skiing.
Scandinavian Journal of Medicine & Science in Sports.
ISSN 0905-7188.
24(4),
p. 667–677.
doi:
10.1111/sms.12038.
Show summary
We have limited insight into how injuries occur in professional ski racing. The aim of this study was to describe the injury situations in World Cup alpine skiing. Injuries reported through the International Ski Federation Injury Surveillance System for three consecutive World Cup seasons (2006–2009) were obtained on video. In total, 69 injuries and 124 runs of matched controls were analysed by five experts to evaluate the skiing situation, skier behavior, as well as piste-related factors. A chi-square test (95% CI, P ≤ 0.05) was used to examine whether there was a difference between course sections regarding where the injury situation occurred. The skier was most frequently turning (n = 55) or landing from a jump (n = 13) at the time of injury. Most of the injuries to the head and upper body (96%) resulted from crashes, while the majority of knee injuries (83%) occurred while the skier was still skiing. Gate contact contributed to 30% of the injuries, while 9% occurred at contact with safety nets/material. Almost half of the injuries (46%) occurred in the final fourth of the course. A particular concern was the high contribution of inappropriate gate contact and the high-energy impacts to the body when crashing.
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Haugen, Per
(1999).
Alpint/Telemark.
In Enoksen, Eystein (Eds.),
Aktivitetslære : grunnbok : studieretning for idrettsfag.
Gyldendal Undervisning.
ISSN 8205248028.
p. 408–451.
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Morstad, Marius; Haugen, Per & Henriksen, Per
(1999).
Skibruken i Forsvaret — i et blindspor?
In Sookermany, Anders McD (Eds.),
Kunnskap om idrett : Tema: Fysisk yteevne — ingen operativ betydning.
Norges idrettshøgskole.
ISSN 0809-0890.
p. 91–99.
Show summary
Bruk av ski i Forsvaret har vært kraftig på retur i norske hæravdelinger de siste årene. Dette har en naturlig forklaring i den generelle utviklingen av den moderne krigføring vinterstid. Med bruk av beltevogner og snøscootere kan avdelingene raskere bli transportert fram til stridsområdet. Forflytning på ski har i en viss grad forspilt sin rolle for større avdelinger, men for jeger- og spesialavdelinger med oppdrag blant annet i ulent terreng kan skiene være et nyttig hjelpemiddel. Skiutstyret som brukes i Forsvaret i dag holder på mange måter ikke mål for slike oppdrag. Det arbeides derfor med utvikling av nytt skiutstyr. I artikkelen beskrives de erfaringer som er gjort, og hvilke krav som må stilles blant annet til ski, binding og støvler.
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Reid, Robert C.; Tjørhom, Håvard; Moger, Tron; Haugen, Per; Kipp, Ronald & Smith, Gerald A.
(2007).
Accuracy of 3d position prediction over a large object space volume using pan and tilt cameras.
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Reid, Robert C. & Haugen, Per
(2005).
The planning of training for highly qualified alpine ski racers: The philosophies of expert coaches.
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Introduction Much has been written on the theory of training and certain principles have gained acceptance in the literature. However, difficulties can arise in the actual planning of training that can make the application of these principles not always as straight-forward as it would seem. For instance, in the sport of alpine ski racing there are numerous practical considerations which seem to play a significant role in planning. The purpose of this study was to examine the philosophies of expert coaches regarding the design of the annual plan for highly qualified alpine ski racers and to compare these philosophies with the principles espoused in the literature. Methods In-depth interviews as described by Kvale (1996) were conducted with fourteen expert coaches from six different countries ? AUT, SUI, USA, SWE, NOR, and SLO. Each of the interviews was transcribed to text for further study. Grounded theory as described by Strauss & Corbin (1998) was used as the theoretical basis for the analysis of the interview data. Results & Discussion A number of similarities and differences between the literature and philosophies of coaches became apparent over the course of the interview analysis. It appears that the ?Classical Periodization Model? (Balyi, 1992) has had a significant impact on the planning of training in alpine ski racing, at least as far as the preparation period is concerned. The principles of load progression, moderation, continuous load demand, variety, multi-lateral development, and specificity were all applied in the planning of the preparation period. However, during the competition period things became much more complex due to the instability of the weather and competition calendar. Thus, while training plans during the preparation period appeared fairly structured and systematic, it seemed that a more flexible planning model was needed during the competition period. A second difference from the Classical Periodization Model was the lack of a major transition period following the competition period. A third finding of interest was that equipment testing and development ? which is rarely mentioned in the literature - is a critical aspect of preparation and should be included in planning. References Balyi, I. (1992). Beyond Barcelona: 4th Elite Coaches Seminar, Canberra, Australia. Kvale, S. (1996). Interviews. Strauss, A. & Corbin, J. (1998). Basics of qualitative research (2nd ed.).
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Reid, Robert C. & Haugen, Per
(2005).
The planning of training for highly qualified alpine ski racers : the philosophies of expert coaches.
Show summary
Introduction: Much has been written on the theory of training and certain principles have gained acceptance in the literature. However, difficulties can arise in the actual planning of training that can make the application of these principles not always as straight-forward as it would seem. For instance, in the sport of alpine ski racing there are numerous practical considerations which seem to play a significant role in planning. The purpose of this study was to examine the philosophies of expert coaches regarding the design of the annual plan for highly qualified alpine ski racers and to compare these philosophies with the principles espoused in the literature. Methods: In-depth interviews as described by Kvale (1996) were conducted with fourteen expert coaches from six different countries – AUT, SUI, USA, SWE, NOR, and SLO. Each of the interviews was transcribed to text for further study. Grounded theory as described by Strauss & Corbin (1998) was used as the theoretical basis for the analysis of the interview data. Results & Discussion: A number of similarities and differences between the literature and philosophies of coaches became apparent over the course of the interview analysis. It appears that the “Classical Periodization Model” (Balyi, 1992) has had a significant impact on the planning of training in alpine ski racing, at least as far as the preparation period is concerned. The principles of load progression, moderation, continuous load demand, variety, multi-lateral development, and specificity were all applied in the planning of the preparation period. However, during the competition period things became much more complex due to the instability of the weather and competition calendar. Thus, while training plans during the preparation period appeared fairly structured and systematic, it seemed that a more flexible planning model was needed during the competition period. A second difference from the Classical Periodization Model was the lack of a major transition period following the competition period. A third finding of interest was that equipment testing and development – which is rarely mentioned in the literature - is a critical aspect of preparation and should be included in planning. References: Balyi, I. (1992). Beyond Barcelona: 4th Elite Coaches Seminar, Canberra, Australia. Kvale, S. (1996). Interviews. Strauss, A. & Corbin, J. (1998). Basics of qualitative research (2nd ed.).
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Morstad, Marius; Haugen, Per & Henriksen, Per
(1999).
Skibruken i Forsvaret — i et blindspor?
Norges idrettshøgskole.
Show summary
Bruk av ski i Forsvaret har vært kraftig på retur i norske hæravdelinger de siste årene. Dette har en naturlig forklaring i den generelle utviklingen av den moderne krigføring vinterstid. Med bruk av beltevogner og snøscootere kan avdelingene raskere bli transportert fram til stridsområdet. Forflytning på ski har i en viss grad forspilt sin rolle for større avdelinger, men for jeger- og spesialavdelinger med oppdrag blant annet i ulent terreng kan skiene være et nyttig hjelpemiddel. Skiutstyret som brukes i Forsvaret i dag holder på mange måter ikke mål for slike oppdrag. Det arbeides derfor med utvikling av nytt skiutstyr. I artikkelen beskrives de erfaringer som er gjort, og hvilke krav som må stilles blant annet til ski, binding og støvler.
View all works in Cristin
Published
Oct. 17, 2023 1:12 PM
- Last modified
Dec. 13, 2023 2:35 PM