Search results for "hiihto"

Balance Perturbations as a Measurement Tool for Trunk Impairment in Cross-Country Sit Skiing

2018

In cross-country sit-skiing, the trunk plays a crucial role in propulsion generation and balance maintenance. Trunk stability is evaluated by automatic responses to unpredictable perturbations; however, electromyography is challenging. The aim of this study was to identify a measure to group sit-skiers according to their ability to control the trunk. Seated in their competitive sit-ski, 10 male and 5 female Paralympic sit-skiers received 6 forward and 6 backward unpredictable perturbations in random order. k-means clustered trunk position at rest, delay to invert the trunk motion, and trunk range of motion significantly into 2 groups. In conclusion, unpredictable perturbations might quantif…

Technical determinants of biathlon standing shooting performance before and after race simulation

2018

The aim of this study was to identify performance- determining factors in biathlon standing shooting in rest and after intense exercise. Eight Finnish national- and nine junior- team biathletes participated in the study. Participants fired 40 resting shots (REST) and 2 × 5 competition simulation shots (LOAD) after 5 minutes of roller skiing at 95% of peak heart rate. Hit percentage, aiming point trajectory and postural balance were measured from each shot. Cleanness of triggering (ATV, movement of the aiming point 0- 0.2 second before the shot) and vertical stability of hold (DevY) were the most important components affecting shooting performance both in REST (DevY, R = −0.61, P < .01; ATV,…

Performance‐determining factors in biathlon prone shooting without physical stress

2021

This study investigated the most important factors determining biathlon prone shooting performance. 10 female and 16 male biathletes (age 19.9 ± 2.9 years) from the national teams of Finland and Vuokatti-Ruka Sports Academy performed 65 biathlon prone shooting shots without physical stress under laboratory conditions. Shooting performance and multiple aiming point trajectory variables were measured together with an analysis of triggering force. Based on the aiming point trajectory data principal component analysis, we identified four technical components in biathlon prone shooting: stability of hold, aiming accuracy, cleanness of triggering and timing of triggering. Multiple regression anal…

Leisure-time cross-country skiing and risk of atrial fibrillation and stroke:a prospective cohort study

2020

[No Abstract]

Changes in biomechanics of skiing at maximal velocity caused by simulated 20 km skiing race using V2 skating technique

2017

This study investigated how the fatigue caused by a 20 km simulated skating cross-country skiing race on snow affects the final spurt performance from a biomechanical perspective. Subjects performed a 100 meter maximal skiing trial before and at the end of the simulated race. Cycle characteristics, ground reaction forces from skis and poles, and muscle activity from eight muscles were recorded during each trial. Results showed that subjects were in a fatigued state after the simulated race manifested by 11.6% lower skiing speed (P < 0.01). The lower skiing speed was related to an 8.0% decrease in cycle rate (P < 0.01) whereas cycle length was slightly decreased (tendency). In temporal patte…

Arm swing during skating at different skiing speeds affects skiing mechanics and performance

2018

Fascicle-tendon interaction in v2 skate cross-country skiing : a case study

2015

Venymis-lyhenemis –sykli (SSC) on laajalti tutkittu liha-jänne -kompleksin (MTU) toimintamalli ihmisen liikkumisessa. Jotta SSC toiminta voidaan ymmärtää, lihaksen toiminta tulee mitata ultraäänen (US) avulla. Aiemmin yksi tutkimus on käsitellyt MTU:n toimintaa hiihdon aikana perinteisellä hiihtotavalla (Ishikawa, Sano et al. 2010). Tämän tutkimuksen tavoitteena on tarjota ainutlaatuinen kokeellinen tulos MTU:n toiminnasta vapaan hiihdon V2- tekniikan aikana, sekä tarjota suosituksia tulevaa tutkimusta varten. Tutkimuksessa yksi kokenut hiihtäjä suoritti protokolla Vuokatin hiihtotunnelissa. Protokolla koostui kahdesta eri mittauskerrasta, joiden välissä suoritettiin 20 km mittainen hiihtok…

Physical performance, heart rate variability and hormone concentrations in cross-country skiers throughout the season

2016

Cross-country skiing is an extremely demanding and versatile competitive sport. Fairly little is known about changes in basal hormonal concentrations and function of the autonomic nervous system throughout the season. Better understanding about these changes as well as their relationship to changes in physical performance and training could be useful for designing better training practices and periodization. This study followed 22 national level cross-country skiers (12 men, 10 women) throughout one competitive season. They were tested at the beginning of the season, during the general preparation season, during the specific preparation season and after the competition season for physical p…

Funktio-EMG-arvojen yhteys alaselkäongelmiin maastohiihtäjillä

2005

Force Generation Profiles of Para-Nordic Sit-Skiers Representing Different Physical Impairments

2021

Abstract Purpose To biomechanically profile force generation connected to the complex role of the trunk in double poling in a representative sample of Para-Nordic sit-skiers. Methods Twelve male World Cup Para-Nordic sit-skiers (sport classes: LW10–12) were skiing on flat snow terrain at submaximal speed of 4.5 m/s (~ 73% maximum speed). 2D video (50 Hz) and pole force analyses (1000 Hz) were performed synchronously, examining angle, force and cycle characteristics to analyse the role of the trunk in generating propulsion. Results LW10–11.5 skiers lost between 21% and 4% propulsive force versus LW12 athletes only due to different geometrics of the trunk and pole angle at an equal axial pole…