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Cross country ski

C Zoppirolli, B Pellegrini, R Modena, A Savoldelli, L Bortolan, F Schena
This study evaluated muscle activity changes in different body compartments during on-snow double poling at increasing velocities. 21 well-trained, male cross-country skiers performed five 3-min double poling trials on a snowy track at 15, 16.5, 18, 19.5, and 21 km/h (set by an audio-pace system). A sixth trial was performed by maintaining a constant maximal speed. Actual skiing velocities were verified using a photocell system. Only 11 subjects met the pre-defined inclusion criteria during the trials and were included in the data analysis...
October 10, 2016: Scandinavian Journal of Medicine & Science in Sports
Thomas Losnegard, Håvard Myklebust, Angela Ehrhardt, Jostein Hallén
To characterise timing of movements and evaluate performance effects of technique alterations in V2 ski skating, 13 elite male cross-country skiers (age, 23 ± 2 years; stature, 182 ± 6 cm; body mass, 76 ± 8 kg; V2 V̇O2max, 79.3 ± 4.4 mL · kg(-1) · min(-1)) were tested four times during the preparation and competition phase on a roller ski treadmill. Each test consisted of submaximal intensities of exercise for determination of oxygen cost followed by one 1000-m performance test. Hip movement (from accelerometer data) and joint angles (2D video) were determined for high-intensity exercise (6° and 3...
August 11, 2016: Journal of Sports Sciences
Cristina Gonzalez-Millan, Dario Perez-Brunicardi, Juan Jose Salinero, Beatriz Lara, Javier Abián-Vicen, Francisco Areces, Diana Ruiz-Vicente, Lidon Soriano, Juan Del Coso
The aim of this study was to assess different physiological variables before and after a 5 km (women) and 10 km (men) cross-country skiing competition to determine potential mechanisms of fatigue. Fourteen elite-level skiers competed in an official cross-country skiing competition using the classical style (9 men and 5 women). Instantaneous skiing velocity was measured during the race by means of 15-Hz GPS devices. Before and after the race, a sample of venous blood was obtained to assess changes in blood lactate and serum electrolyte and myoglobin concentrations...
August 18, 2016: Journal of Strength and Conditioning Research
Øyvind Sandbakk, Thomas Losnegard, Øyvind Skattebo, Ann M Hegge, Espen Tønnessen, Jan Kocbach
The present study investigated the contribution of performance on uphill, flat, and downhill sections to overall performance in an international 10-km classical time-trial in elite female cross-country skiers, as well as the relationships between performance on snow and laboratory-measured physiological variables in the double poling (DP) and diagonal (DIA) techniques. Ten elite female cross-country skiers were continuously measured by a global positioning system device during an international 10-km cross-country skiing time-trial in the classical technique...
2016: Frontiers in Physiology
Erik Andersson, Hans-Christer Holmberg, Niels Ørtenblad, Glenn Björklund
PURPOSE: To examine the metabolic responses and pacing strategies during the performance of successive sprint time trials (STTs) in cross-country skiing. METHODS: Ten well-trained male cross-country skiers performed four self-paced 1300-m STTs on a treadmill, each separated by 45 min of recovery. The simulated STT course was divided into three flat (1°) sections (S1, S3 and S5) involving the double poling sub-technique interspersed with two uphill (7°) sections (S2 and S4) involving the diagonal stride sub-technique...
July 12, 2016: Medicine and Science in Sports and Exercise
Benedikt Fasel, Caroline Praz, Bengt Kayser, Kamiar Aminian
In this study an algorithm designed for the diagonal stride in classical cross-country skiing was adapted to compute spatio-temporal parameters for uphill ski mountaineering using a ski fixed inertial sensor. Cycle duration, thrust duration, cycle speed, cycle distance, elevation gain, and slope angle were computed and validated against a marker-based motion capture system during indoor treadmill skiing. Skiing movement of 12 experienced, recreational level athletes was measured for nine different speed and slope angle combinations...
June 23, 2016: Journal of Biomechanics
Kim Hébert-Losier, Christoph Zinner, Simon Platt, Thomas Stöggl, Hans-Christer Holmberg
BACKGROUND: Sprint events in cross-country skiing are unique not only with respect to their length (0.8-1.8 km), but also in involving four high-intensity heats of ~3 min in duration, separated by a relatively short recovery period (15-60 min). OBJECTIVE: Our aim was to systematically review the scientific literature to identify factors related to the performance of elite sprint cross-country skiers. METHODS: Four electronic databases were searched using relevant medical subject headings and keywords, as were reference lists, relevant journals, and key authors in the field...
June 22, 2016: Sports Medicine
W Derman, M P Schwellnus, E Jordaan, P Runciman, P Van de Vliet, C Blauwet, N Webborn, S Willick, J Stomphorst
OBJECTIVE: To describe the epidemiology of injuries at the Sochi 2014 Winter Paralympic Games. METHODS: A total of 547 athletes from 45 countries were monitored daily for 12 days during the Sochi 2014 Winter Paralympic Games (6564 athlete days). Daily injury data were obtained from teams with their own medical support (32 teams, 510 athletes) and teams without their own medical support (13 teams, 37 athletes) through electronic data capturing systems. RESULTS: There were 174 total injuries reported, with an injury incidence rate (IR) of 26...
September 2016: British Journal of Sports Medicine
G Boccia, D Dardanello, C Zoppirolli, L Bortolan, C Cescon, A Schneebeli, G Vernillo, F Schena, A Rainoldi, B Pellegrini
Although elbow extensors (EE) have a great role in cross-country skiing (XC) propulsion, previous studies on neuromuscular fatigue in long-distance XC have investigated only knee extensor (KE) muscles. In order to investigate the origin and effects of fatigue induced by long-distance XC race, 16 well-trained XC skiers were tested before and after a 56-km classical technique race. Maximal voluntary isometric contraction (MVC) and rate of force development (RFD) were measured for both KE and EE. Furthermore, electrically evoked double twitch during MVC and at rest were measured...
June 12, 2016: Scandinavian Journal of Medicine & Science in Sports
Agnes Mägi, Eve Unt, Ele Prans, Liina Raus, Jaan Eha, Alar Veraksitš, Külli Kingo, Sulev Kõks
Endurance performance depends on the integration of several phenotypic traits influenced by multiple environmental and genetic factors. Objectives of the study were: (1) to examine the genotypic frequencies of the ACE I/D, ACTN3 R577X polymorphisms and endurance performance-related phenotypes, (2) to evaluate the dynamics of endurance performance parameters during a 5-year period in relation to ACE I/D and ACTN3 R577X genotypes in Estonian young skiers. Determination of VO2peak was performed in 58 skiers aged 15-19 years (41 males, 17 females) during a 5-year period...
June 2016: Journal of Sports Science & Medicine
I O Garnov, A V Kuchin, T P Loginova, N G Varlamova, E R Boiko
The baths with emulsified turpentine find the wide application in balneotherapy. They produce especially pronounced beneficial prophylactic effects in the patients presenting with microtrombosis and microvascular stasis. Moreover, these baths may be prescribed to improve microcirculation, increase the functional reserves and physical capacity in the athletes. At the same time, the current literature appears to contain no scientific publications on the application of emulsified turpentine baths for the restoration of the physical capacity of the professional ski runners...
March 2016: Voprosy Kurortologii, Fizioterapii, i Lechebnoĭ Fizicheskoĭ Kultury
Conor M Bolger, Øyvind Sandbakk, Gertjan Ettema, Peter Federolf
The purposes of the current study were to 1) test if the hinge position in the binding of skating skis has an effect on gross efficiency or cycle characteristics and 2) investigate whether hinge positioning affects synergistic components of the muscle activation in six lower leg muscles. Eleven male skiers performed three 4-min sessions at moderate intensity while cross-country ski-skating and using a klapskate binding. Three different positions were tested for the binding's hinge, ranging from the front of the first distal phalange to the metatarsal-phalangeal joint...
2016: PloS One
Thomas Losnegard, Håvard Myklebust, Øyvind Skattebo, Hans Kristian Stadheim, Øyvind Sandbakk, Jostein Hallén
PURPOSE: In the double poling cross-country skiing technique, the propulsive forces are transferred solely through the poles. The aim of the present study was to investigate how pole length influences double poling performance, O2-cost and kinematics during treadmill roller skiing. METHODS: Nine male competitive cross-country skiers (24±3 yrs, 180±5 cm, 72±5 kg, VO2max running: 76±6 mL·kg-1·min-1) completed two identical test protocols using self-selected (84±1% of body height) and long poles (self-selected + 7...
May 18, 2016: International Journal of Sports Physiology and Performance
Geneviève Masson, Benoît Lamarche
Little is known regarding the dietary intake of non-elite athletes involved in multisport endurance events. The primary objective of this observational study was to characterize the dietary intake of non-elite athletes participating in winter triathlon (snowshoeing, skating, and cross-country skiing), winter pentathlon (winter triathlon sports + cycling and running), Ironman (IM: swimming, cycling, running), and half-distance Ironman (IM 70.3) in relation with current sports nutrition recommendations. A total of 116 non-elite athletes (32 women and 84 men) who had participated in one of those events in 2014 were included in the analyses...
July 2016: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Victor Wennemar Wiltmann, Hans-Christer Holmberg, Pasi Pelttari, Jussi Mikkola, Keijo Häkkinen, Olli Ohtonen, Vesa Linnamo
The present study was designed to analyse and compare the kinetics and kinematics associated with three different starting strategies during classic cross-country ski racing. Inside a ski tunnel, 12 elite male skiers performed three sets of three 38 m starts. Each set included one start using: double poling only (DP), diagonal stride only (DIA) and freely chosen (FREE) (i.e. where subjects used the strategy or combination of strategies they felt was fastest) in random order. The first 18 m was performed on a series of force plates that measured horizontal and vertical forces followed by 20 m of a standard snow track...
November 2016: European Journal of Sport Science
Yoshihisa Sakurai, Zenya Fujita, Yusuke Ishige
This study aims to develop and validate an automated system for identifying skating-style cross-country subtechniques using inertial sensors. In the first experiment, the performance of a male cross-country skier was used to develop an automated identification system. In the second, eight male and seven female college cross-country skiers participated to validate the developed identification system. Each subject wore inertial sensors on both wrists and both roller skis, and a small video camera on a backpack...
2016: Sensors
Thomas Leonhard Stöggl, Hans-Christer Holmberg
INTRODUCTION: In light of the recent revolutionary change in the use of the double-poling (DP) technique in cross-country skiing, our purpose was to compare the associated kinetics and kinematics on flat (DPflat) and uphill terrain (DPup), as well as to identify factors that determine performance. METHODS: Thirteen elite male cross-country skiers completed two incremental speed tests (Vpeak) involving roller skiing with the DP technique at moderate (13 and 24 km·h) and high speed (15 and 28...
August 2016: Medicine and Science in Sports and Exercise
Caroline Göpfert, Stefan J Lindinger, Olli Ohtonen, Walter Rapp, Erich Müller, Vesa Linnamo
The study investigated the effects of arm swing during leg push-off in V2-alternate/G4 skating on neuromuscular activation and force production by the leg muscles. Nine skilled cross-country skiers performed V2-alternate skating without poles at moderate, high, and maximal speeds, both with free (SWING) and restricted arm swing (NOSWING). Maximal speed was 5% greater in SWING (P<0.01), while neuromuscular activation and produced forces did not differ between techniques. At both moderate and high speed the maximal (2% and 5%, respectively) and average (both 5%) vertical force and associated impulse (10% and 14%) were greater with SWING (all P<0...
June 2016: Human Movement Science
Thomas Stöggl, Alex Martiner
The purpose of this study was the experimental validation of the OpenGo sensor insole system compared to PedarX sensor insole and AMTI force-plate systems. Sixteen healthy participants performed trials in walking, running, jumping (drop and counter movement jumps), imitation drills and balance, with simultaneous measures of all three systems. Detected ground contact and flight times with OpenGo during walking, running and jumping were similar to those of AMTI. Force-time curves revealed comparable shapes between all three systems...
March 24, 2016: Journal of Sports Sciences
Thomas Losnegard, Kasper Kjeldsen, Øyvind Skattebo
Understanding the pacing strategies employed by the most successful skiers may provide insight into the most desirable pacing approach in cross-country skiing. This study examined the pacing strategies adopted by male and female cross-country skiers of different performance standards during 10/15 km races in World Cup, World Championship and Olympic events. Analyses were carried out on races involving 5 km laps in the men's 15 km (number of races = 22) and the women's 10 km (n = 14) individual start races (classic and free style) from season 2002/2003 to season 2013/2014...
March 12, 2016: Journal of Strength and Conditioning Research
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