miun.sePublications
Change search
Refine search result
1 - 29 of 29
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Roller skis' rolling resistance and grip characteristics: influences on physiological and performance measures in cross-country skiers2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim of this thesis was to investigate roller ski characteristics; classical and freestyle roller skis’ rolling resistance coefficients (μR) and classical style roller skis’ static friction coefficients (μS), and to study the influence of different μR and μS on cross-country skiers’ performance and both physiological and biomechanical indices. The aim was also to study differences in skiing economy and efficiency between recreational skiers, female and male junior and senior elite cross-country skiers.The experiments showed that during a time period of 30 minutes of rolling on a treadmill (warm-up), μR decreased significantly (p<0.05) to about 60-65 % and 70-75 % of its initial value for freestyle and classical roller skis respectively. Also, there was a significant influence of normal force on μR, while different velocities and inclinations of the treadmill only resulted in small changes in μR.The study of the influence on physiological variables of a ~50 % change in μR showed that during submaximal steady rate exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non-significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a change in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non-significant or small.The study of classical style roller skis μS showed values that were five to eight times more than the values of μS reported from on-snow skiing with grip-waxed cross-country skis.The subsequent physiological and biomechanical experiments with different μS showed a significantly lower skiing economy (~14 % higher v̇O2), higher heart rate, lower propulsive forces coming from the legs and shorter time to exhaustion (~30 %) when using a different type of roller ski with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a (similar) higher μS.The part of the thesis which focused on skiing economy and efficiency as a function of skill, age and gender, showed that the elite cross-country skiers had better skiing economy and higher gross efficiency (5-18 %) compared with the recreational skiers, and the senior elite had better economy and higher efficiency (4-5 %) than their junior counterparts, while no differences could be found between the genders.

  • 2.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    The rolling resistances of roller skis and their effects on human performance during treadmill roller skiing2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical performance in a laboratory environment using classical and freestyle techniques on roller skis. For elite athletes the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance coefficient, µR, in order to allow correct comparisons between the results, as well as providing the opportunity to study work economy between different athletes, test occasions and core techniques.

    Thus, one of the aims of this thesis was to evaluate how roller skis’ µR is related to warm-up, mass, velocity and inclination of the treadmill. It was also necessary to investigate the methodological variability of the rolling resistance measurement system, RRMS, specially produced for the experiments, with a reproducibility study in order to indicate the validity and reliability of the results.

    The aim was also to study physiological responses to different µR during roller skiing with freestyle and classical roller skis and techniques on the treadmill as a case in which all measurements were carried out in stationary and comparable conditions.

    Finally, the aim was also to investigate the work economy of amateurs and female and male junior and senior cross-country skiers during treadmill roller skiing, i.e. as a function of skill, age and gender, including whether differences in body mass causes significant differences in external power per kg due to differences in the roller skis’ µR.

    The experiments showed that during a warm-up period of 30 minutes, µR decreased to about 60-65% and 70-75% of its initial value for freestyle and classical roller skis respectively. For another 30 minutes of rolling no significant change was found. Simultaneous measurements of roller ski temperature and mR showed that stabilized mR corresponds to a certain running temperature for a given normal force on the roller ski. The study of the influence on mR of normal force, velocity and inclination produced a significant influence of normal force on mR, while different velocities and inclinations of the treadmill only resulted in small changes in mR. The reproducibility study of the RRMS showed no significant differences between paired measurements with either classical or the freestyle roller skis.

    The study of the effects on physiological variables of ~50% change in µR,showed that during submaximal steady state exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a significantly changed maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non significant or small.

    The final part of the thesis, which focused on work economy, found no significant difference between the four groups of elite competitors, i.e. between the two genders and between the junior and senior elite athletes. It was only the male amateurs who significantly differed among the five studied groups. The study also showed that the external power per kg was significantly different between the two genders due to differences in body mass and mR, i.e. the lighter female testing groups were roller skiing with a relatively heavier rolling resistance coefficient compared to the heavier testing groups of male participants.

  • 3.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Roller ski rolling resistance and its effects on elite athletes’ performance2008In: ENGINEERING OF SPORT 7, VOL 2, 2008, Vol. 11, no 3, p. 393-400Conference paper (Refereed)
    Abstract [en]

    Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical fitness in a laboratory environment whilst performing classical and freestyle (skating) techniques on roller skis. For elite athletes the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance in order to allow the correct comparison between the results of different test occasions. In this study the roller skis’ rolling resistance has been measured using equipment on the ski-treadmill. The study investigates the influence of significant changes in rolling resistance on physiological variables. The results show that during submaximal exercise, heart rate, blood lactate, power and oxygen uptake are significantly changed by different rolling resistances, while there are no significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests show that time to exhaustion is significantly changed by different rolling resistances and this occurred without significant changes in maximal oxygen uptake and heart rate, and the influence on maximal power and ratings of perceived exertion were insignificant or small.

  • 4.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Roller ski rolling resistance and its effects on elite athletes’ performance2009In: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 11, no 3, p. 143-157Article in journal (Refereed)
    Abstract [en]

    Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical fitness in a laboratory environment whilst performing classical and freestyle (skating) techniques on roller skis. For elite athletes, the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance in order to allow the correct comparison between the results of different test occasions. In this study, the roller skis’ rolling resistance was measured on the ski-treadmill’s surface using a roller ski rolling resistance measurement system specially produced for this purpose. The study investigated the influence of significant changes in rolling resistance on physiological variables. The results showed that during submaximal exercise, power, oxygen uptake, heart rate and blood lactate were significantly changed by different rolling resistances, while there were no significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed by different rolling resistances and this occurred without significant changes in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion were insignificant or small.

     

  • 5.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Rolling resistance for treadmill roller skiing2008In: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 11, no 1, p. 23-29Article in journal (Refereed)
    Abstract [en]

    Modern treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical performance under laboratory conditions using classical and freestyle techniques on roller skis. The differences in performance between tests are quite small for elite athletes, and it is therefore of great importance to control the rolling resistance of the roller skis. Otherwise different physiological tests cannot be accurately compared.

    This study shows that during a warm-up period of  30 minutes the coefficient of rolling resistance (µR) decreases to about 60-65% and 70-75% of its initial value for freestyle and classical roller skis respectively.

    Simultaneous measurements of temperature and µR shows that stabilized rolling resistance corresponds to a certain running temperature for a given normal force on the roller ski.

    Tests were also performed on the influence on µR of normal force, velocity and inclination. Normal forces produced significant influence on µR , while different velocities and inclinations of the treadmill only resulted in small changes in µR.

  • 6.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Laaksonen, Marko
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Work economy of amateur and elite cross-country skiers during treadmill roller skiing2009In: 4th Asia Pacific Congress on Sports Technology, APCST2009, 2009Conference paper (Refereed)
    Abstract [en]

    This study focused on the work economy of cross-country skiers during treadmill roller skiing in the perspectives; skill, age and gender. The study was investigating the external power output from elevating the transported mass against gravity and overcoming the roller skis rolling resistance, and the internal power from measured oxygen uptake and energy consumption. The roller skis rolling resistance was measured with a fixture on the ski-treadmill and the results showed a significant correlation between normal force and rolling resistance. The results also showed that it was only the amateur skiers who significantly differed in work economy among the five studied groups.

  • 7.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Laaksonen, Marko S.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    The influence of grip on oxygen consumption and leg forces when using classical style roller skis2014In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, no 2, p. 301-310Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate the influence of classical style roller skis' grip (static friction coefficients, μ S) on cross-country skiers' oxygen consumption and leg forces during treadmill roller skiing, when using the diagonal stride and kick double poling techniques. The study used ratcheted wheel roller skis from the open market and a uniquely designed roller ski with an adjustable camber and grip function. The results showed significantly (P≤0.05) higher oxygen consumption (∼14%), heart rate (∼7%), and lower propulsive forces from the legs during submaximal exercise and a shorter time to exhaustion (∼30%) in incremental maximal tests when using roller skis with a μ S similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a similar, higher μ S. Thus, we concluded that oxygen consumption (skiing economy), propulsive leg forces, and performance time are highly changed for the worse when using roller skis with a lower μ S, such as for on-snow skiing with grip-waxed cross-country skis, in comparison to ratcheted wheel roller skis with several times higher μ S.

  • 8.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    A portable roller ski rolling resistance measurement system2013In: The Impact of Technology on Sport V: Procedia Engineering / [ed] Subic A, Fuss FK, Clifton P, Chan KM., Elsevier, 2013, p. 79-83Conference paper (Refereed)
    Abstract [en]

    Roller skis are used by cross-country skiers, biathletes and ski-orienteers for their snow-free training and in roller ski competitions. Additionally, much of the current sports research into the physiology and biomechanics of crosscountry skiing is conducted indoors on treadmills using roller skis. For elite athletes, the differences in performance are quite small, thus emphasising the importance of knowing the roller skis' rolling resistance coefficient, especially in connection to research and roller ski competitions. The purpose of this study was to develop a roller ski rolling resistance measurement system (P-RRMS) that is portable and therefore useful in different contexts and locations. The P-RRMS was designed as a small treadmill, equipped with roller ski stabilizing lateral supports and a screwed bar for applying different vertical loads on the roller ski. The design uses only one force sensor, with possible measurements of three directions of force and torque around three axes. The weight of the P-RRMS is 100 kg and it is equipped with wheels to facilitate transportation.

  • 9.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    An experimental study to compare the grip of classical style roller skis with on-snow skiing2013In: Sports Engineering, ISSN 1369-7072, E-ISSN 1460-2687, Vol. 16, no 2, p. 115-122Article in journal (Refereed)
    Abstract [en]

    Cross-country skiers use roller skis for their snow-free training with the aim of imitating skiing on snow. Also, exercise laboratories evaluate the biomechanics and physiology of cross-country skiing using roller skis on a treadmill. The roller skis on the market that are constructed for use in the classical style are equipped with a front and a back wheel, one of which has a ratchet to enable it to grip the surface when diagonal striding and kick double poling (static friction). The aim of this study was to investigate static friction coefficients (μS) of ratcheted wheel roller skis, and compare the results to the μS reported from skiing on snow with grip-waxed cross-country skis. Also, a new type of roller ski with a camber and adjustable grip function was evaluated. The results showed that ratcheted wheel roller skis, on a treadmill rubber mat and on dry and wet asphalt surfaces, reached μS values that were five to eight times greater than the values reported from on-snow skiing with grip-waxed cross-country skis. For the roller skis with a camber and adjustable grip function, the μs could be varied from no grip at all up to the level of the tested ratcheted wheel roller skis.

  • 10.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Classical style constructed roller skis and grip functionality2011In: Procedia Engineering: The Impact of Technology on Sports IV / [ed] Subic A., Fuss F.K., Alam F., Clifton P., Elsevier, 2011, p. 4-9Conference paper (Refereed)
    Abstract [en]

    Roller skis are used by cross-country skiers for snow-free training, with the aim of imitating skiing on snow. The roller skis on the market that are constructed for use in the classical style are equipped with a front and a back wheel, one of which has a ratchet to enable it to grip the surface when diagonal striding and kick double poling.

    A new type of roller ski was constructed with a function which makes it necessary to use the same kick technique as that used on snow, i.e. the ski has a camber that must be pushed down to obtain grip. Its stiffness can be adjusted based on factors that influence grip, i.e. the skier’s bodyweight and technical skiing skills.

    Thus, our aim was to make comparative measurements as regards grip between ratcheted roller skis and the roller ski with a camber and compare with previous published results for grip waxed skis during cross-country skiing on snow.  The measurements were carried out using specially developed equipment, with a bottom plate and an overlying rubber mat of the same type as used on many treadmills and a function for applying different loads and generating traction on the back of the roller ski.

  • 11.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Rolling resistance for treadmill roller skiing: Presented at International Congress on Science and Nordic Skiing 2006, June 18-20, 2006, Vuokatti, Finland2006Conference paper (Other academic)
  • 12.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Laaksonen, Marko S.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Skiing economy and efficiency in recreational and elite cross-country skiers2013In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 27, no 5, p. 1239-1252Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate and compare skiing economy and gross efficiency in cross-country skiers of different performance levels, ages and genders; male recreational skiers and elite senior and junior cross-country skiers of both genders. The skiers performed tests involving roller skiing on a treadmill using the gear 3 and diagonal stride techniques. The elite crosscountry skiers were found to have better skiing economy and higher gross efficiency (5-18%) compared with the recreational skiers (p < 0.05) and the senior elite had better economy and higher efficiency (4-5%) than their junior counterparts (p < 0.05), whereas no differences could be found between the genders. Also, large ranges in economy and gross efficiency were found in all groups. It was concluded that, in addition to v̇O2peak, skiing economy and gross efficiency have a great influence on the differences in performance times between recreational and junior and senior elite cross-country skiers, as well as between individual skiers within the different categories. Thus, we recommend crosscountry skiers at all performance levels to test not only v̇O2peak, but also skiing economy and efficiency.

  • 13.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Jensen, Kurt
    Syddansk Universitet, Odense, Danmark.
    Rosdahl, Hans
    Swedish School of Sport and Health Sciences, GIH, Stockholm.
    Breathing resistance in automated metabolic systems is high in comparison with the Douglas Bag method and previous recommendations2018In: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, ISSN 1754-3371, Vol. 232, no 2, p. 122-130Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate the resistance (RES) to breathing in metabolic systems used for the distribution and measurement of pulmonary gas exchange. A mechanical lung simulator was used to standardize selected air flow rates ( , L/s). The delta pressure (∆p, Pa) between ambient air and the air inside the equipment was measured in the breathing valve’s mouthpiece adapter for four metabolic systems and four types of breathing valves. RES for the inspiratory and expiratory sides was calculated as RES = ∆p / , Pa/L/s. The results for RES showed significant (p < 0.05) between-group variance among the tested metabolic systems, as well as the breathing valves and between most of the completed . The lowest RES among the metabolic systems was found for a Douglas Bag system, with approximately half of the RES compared to the automated metabolic systems. The automated systems were found to have higher RES already at low  in comparison to previous recommendations. For the hardware components, the highest RES was found for the breathing valves while the lowest RES was found for the hoses. Conclusion: The results showed that RES in metabolic systems can be minimized through conscious choices of system design and hardware components. 

  • 14.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Jonsson, Patrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Drag Area, Frontal Area and Drag Coefficient in Cross-Country Skiing Techniques2018In: Proceedings, Volume 2, ISEA 2018 / [ed] Hugo Espinosa, David Rowlands, Jonathan Shepherd, David Thiel, MDPI, 2018, Vol. 2, article id 313Conference paper (Refereed)
    Abstract [en]

    The aim of this study was to investigate the air drag, frontal area and coefficient of drag of cross-country skiing classical and free style techniques. One highly skilled cross-country skier performed skiing-like classical and free style techniques on a force plate in a wind tunnel. The skier was also photographed from the front in order to analyze the projected frontal area, which was determined from digital images using Matlab. From the results of the air drag and the frontal area measurements, the drag coefficient was also calculated. The results can be used by researchers to calculate the theoretical effect of air drag on cross-country skiing performance.

  • 15.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    The multi functional roller ski2012Conference paper (Refereed)
  • 16.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Rännar, Lars-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    The multifunctional roller ski2013In: Science and Nordic Skiing II / [ed] Hakkarainen A, Linnamo V, Lindinger S, University of Salzburg, University of Jyväskylä , 2013, p. 253-261Chapter in book (Refereed)
  • 17.
    Ainegren, Mats
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Tuplin, Simon
    Loughborough University, Loughborough, UK.
    Carlsson, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Render, Peter
    Loughborough University, Loughborough, UK.
    Design and development of a climatic wind tunnel for physiological sports experimentation2019In: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology, ISSN 1754-3371, Vol. 233, no 1, p. 86-100Article in journal (Refereed)
    Abstract [en]

    The aim of this project was to develop a wind tunnel that enables the study of human performance during various types ofsports and physical activities by examining the influence of aerodynamic drag, precipitation, frictional forces and gravitationalforces on uphill and downhill travel on a moving substrate. An overall design for a wind tunnel and working section containinga large treadmill was drafted, followed by computational fluid dynamics simulations of flow conditions to assess thedesign’s feasibility and select from different geometries prior to its construction. The flow conditions in the completed windtunnel were validated using different flows, speeds and treadmill inclinations. Pilot experiments were carried out using across-country skier to investigate the effect of aerodynamic drag on oxygen uptake during double poling and the maximalachieved speed when rolling on a declined treadmill. The purpose was to validate the usefulness of the tunnel. The resultsshowed that flow conditions are acceptable for experiments even in worst-case scenarios with maximal inclined and declinedtreadmill. Results also showed that aerodynamic drag has a significant impact on the skier’s energy expenditure.

  • 18.
    Andersson, Fredrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Skoglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Viktorsson, Jan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    A Portable Douglas Bag System2015In: Congress Proceedings: ICSNS 2015 / [ed] Hakkarainen Anni, Lindinger Stefan, Linnamo Vesa, 2015, p. 59-Conference paper (Refereed)
  • 19.
    Carlsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Sundström, David
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Esping, Björn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Koptioug, Andrey
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Cross-Country Ski2015In: The Engineering Approach to Winter Sports / [ed] Braghin F., Cheli F., Maldifassi S., Melzi S. and Sabbioni E., Springer, 2015, p. 107-152Chapter in book (Other academic)
    Abstract [en]

    Cross-country skiing, biathlon and ski orienteering are competitive sports with practitioners who are mostly from countries in the northern hemisphere. The competition season is during the time when the ground is covered with snow, which roughly extends from mid-November to late March. During the rest time of the year, which is a long preparatory period of training for the skiers before the competition season, the skiers use roller skis for dryland training with the aim of imitating skiing on snow. Furthermore, over the last few decades, fairly specific indoor testing methods for cross-country skiers have become possible due to the development of treadmills that allow roller skiing using classical and freestyle techniques.

  • 20.
    Carlsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Numeric Simulation of Cross Country Skiing2009Conference paper (Refereed)
  • 21.
    Carlsson, Peter
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Tinnsten, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Numerical Simulation of Cross Country Skiing2011In: Computer Methods in Biomechanics and Biomedical Engineering, ISSN 1025-5842, E-ISSN 1476-8259, ISSN 1025-5842, Vol. 14, no 8, p. 741-746Article in journal (Refereed)
    Abstract [en]

    A program for numerical simulation of a whole ski race, from start to finish, is developed in MATLAB. The track ismodelled by a set of cubical splines in two dimensions and can be used to simulate a track in a closed loop or with the startand finish at different locations. The forces considered in the simulations are gravitational force, normal force between snowand skis, drag force from the wind, frictional force between snow and ski and driving force from the skier. The differentialequations of motion are solved from start to finish with the Runge–Kutta method. Different wind situations during the racecan be modelled, as well as different glide conditions on different parts of the track. It is also possible to vary the availablepower during the race. The simulation program’s output is the total time of the race, together with the forces and speedduring different parts of the race and intermediate times at selected points. Some preliminary simulations are also presented.

  • 22.
    Koptioug, Andrei
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Nilsson, Kajsa
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Management and Mechanical Engineering.
    Studying Moisture Transport Trough "Active" Fabrics Using Humidity-Temperature Sensor Nodes2018In: Proceedings, Volume 2, ISEA 2018: / [ed] Dr Hugo Espinosa, David R. Rowlands, Jonathan Shepherd, Professor David Thiel, 2018, Vol. 2, p. 230-, article id 6Conference paper (Refereed)
    Abstract [en]

    Active fabrics providing better comfort of the garments and footwear rapidly become an essential part of our life. However, only limited information about the performance of such fabrics is commonly available for the garment and footwear designers, and tests are often done only with the final products. Thus development of the objective testing methods for the fabric assemblies containing microporous membranes and garments using them is one of the important topics. Garment tests in the climate chamber when exercising in windy and rainy conditions with a set of temperature and humidity sensors placed over the body allow comparing manufactured garments for thermal and humidity comfort. To allow for better material testing a new laboratory setup was developed for studying the dynamics of the humidity transport through different fabrics at realistic conditions in extension of the existing ISO test procedure. Present paper discusses the experimental procedures and first results acquired with new setup.

  • 23.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Experimental measurement of rifle dynamics during the range shooting of biathlon weapons2015In: Procedia Engineering: The Impact of Tecnology on Sport VI / [ed] Subic A., Fuss F.K., Alam F., Pang T.Y. and Takla M., Elsevier, 2015, Vol. 112, p. 349-354Conference paper (Refereed)
    Abstract [en]

    Some of the shooting training that biathletes implements takes place indoors, even in hotel rooms or at home, through so-called "dry firing" training. It involves imitating shooting at a target with real rifle but without ammunition, when the result is evaluated by various electronic devices counting the number of virtual hits. But dry firing cannot adequately represent real shooting, as it does not produce any rifle recoil, which significantly limits its value for the training. To reach a higher realism of the dry firing training a system mimicking the weapon recoil is therefore needed. Present research aims to overcome an existing lack of dataon the dynamics ofsmall caliber rifles recoil dynamics. Present paper describes first measurement results acquired in the controlled environment of the shooting range. Two types of experiments were carried out with firing freely suspended rifle and when backed with the force measurement device (load cell). Average recoil peak force values were reaching 5 kg, rising from zero forabout 10-15 ms and keeping altogether for about 30-40 ms. Corresponding energy going into the recoil motion of the rifle is found to be about 390 J. The measured values provide an adequate input for designing the devices mimicking the biathlon weapon recoil in dry firing training.

  • 24.
    Koptyug, Andrey
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Bäckström, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Schieber, Erika
    Persson, Jonas
    Possibility of modern humidity sensor application in the studies ofmoisture transport through the sports and outdoor garments2016In: icSPORTS 2016 - Proceedings of the 4th International Congress on Sport Sciences Research and Technology Support, Portugal: SciTePress, 2016, p. 51-58Conference paper (Refereed)
    Abstract [en]

    Sensor nodes containing pairs of temperature and humidity sensors were assessed as a mean of garmentperformance and comfort studies. Modern sensors are small, low weight and produce minimal disturbancewhen placed under the garments and in the footwear. Four sensor nodes were used to provide dynamicinformation about heat and humidity transfer properties of garments during the tests in realistic conditions.Pilot studies were carried out for the few models of cross country skiing garments and waders. Main studieswere carried out in the wind tunnel at Mid Sweden University having pivoted treadmill, temperature controland rain capacity. Additional experiments with the waders were carried out in a large water tank. Studies ofthe temperature and humidity dynamics under the garments containing microporous membranes illustratethe importance of recognizing main features of such materials. In particular, such membranes can onlytransport moisture from the side where humidity is higher. It means that garments and footwear containingsuch membranes will potentially behave differently when ambient air humidity changes. In particular,modern garments with incorporated microporous membranes being superior at low ambient air humidity canbe dramatically less effective for moisture transfer from the body in the rain.

  • 25.
    Laaksonen, Marko
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Lisspers, Jan
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Effects of combined relaxation and shooting training on shooting performance in biathlon2009In: Effects of combined relaxation and shooting training on shooting performance in biathlon, 2009Conference paper (Refereed)
  • 26.
    Laaksonen, Marko
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Lisspers, Jan
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Evidence of improved shooting precision in biathlon after 10-weeks of combined relaxation and specific shooting training2011In: Cognitive Behaviour Therapy, ISSN 1650-6073, E-ISSN 1651-2316, Vol. 40, no 4, p. 237-250Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to test the hypothesis that a combined relaxation (applied tension release, ATR) and specific shooting training regimen may enhance shooting ability of biathlon athletes. Seven biathletes of high national level were randomized into an experimental group (age 20 ± 5 years; Vo 2max 60 ± 8 mL kg− 1 min− 1) and were asked to add this special training intervention to their regular training for 10 weeks, while five other biathletes served as controls (age 19 ± 2 years; Vo 2max 57 ± 10 mL kg− 1 min− 1). The shooting ability of the subjects was assessed before and after the intervention at rest and after roller skiing on a treadmill in a laboratory-based competition simulating assessment. After the intervention period, the experimental group demonstrated a significantly enhanced shooting performance compared to the control group. No changes in Vo 2max or in heart rate and Vo 2 responses were observed before and after the intervention in either group and there were no differences between the groups in these parameters. Thus, the preliminary conclusion is that a combination of ATR and specific shooting training seems to be instrumental in enhancing the shooting performance in biathlon.

  • 27.
    Stöggl, Thomas
    et al.
    Department of Sport Science and Kinesiology, University of Salzburg & Christian Doppler Laboratory, Salzburg, Austria.
    Mueller, Erich
    Department of Sport Science and Kinesiology, University of Salzburg & Christian Doppler Laboratory, Salzburg, Austria.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Holmberg, Hans-Christer
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    General strength and kinetics: fundamental to sprinting faster in cross country skiing?2011In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 21, no 6, p. 791-803Article in journal (Refereed)
    Abstract [en]

    To determine relationships between general strength, maximal skiing speed (16 male elite skiers underwent three double poling, diagonal stride and V2 on a treadmill. The analyzed skiing speeds and leg and arm kinetics were among the highest ever recorded. Relationships between general strength exercises and Power output in bench press and bench pull were related to maximum was related to V2. Isometric squats were not associated with height and rate of force development during squat jump Vmax), pole and leg kinetics and kinematics,Vmax tests inVmax were technique dependent.Vmax in DP and diagonal stride, whereas each 1 repetitionVmax in all three techniques, whereas jump were. Analysis of kinetics and kinematics revealed that it was not exclusively the magnitude of applied forces during skiing, but the timing and proper instant of force application were major factors discriminating between faster and slower skiers. For all techniques, the faster skiers used different skiing strategies when approaching with the slower skiers. General strength and power Vmax when compared per se  seem not to be major determinants of performance in elite skiers, whereas coordination of these capacities within the different and complex skiing movements seems to be the discriminating factor.

  • 28.
    Tesch, Per
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Ainegren, Mats
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Östberg, J
    Swarén, Mikael
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Holmberg, Hans-Christer
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Peak oxygen uptake using a training device for combined resistance and aerobic exercise in space and on earth2008In: 13th Annual Congress of the European College of Sports Science, Cologne: Sportools , 2008, p. 523-Conference paper (Refereed)
    Abstract [en]

    Astronauts traveling in Orbit are mandated to perform both aerobic and resistance exercise to combat cardiovascular and muscular deconditioning. A non-gravity dependent flywheel resistance exercise device (FWD), proven to be effective in blunting muscle atrophy when used by bedridden subjects, has been configured to allow for aerobic exercise as well. The current study aimed at determining aerobic energy yield and related physiological demands during exercise using this novel apparatus. Methods: Eight men and women (23±3 yrs, 65±5 kg, 170±6 cm) performed all-out, indoor, stationary rowing exercise randomly on either a commercially available Concept II ergometer (CII) or the FWD. Using a magnetic brake system, the FWD and similar to the CII, produced mainly concentric resistance exercise with the aid of the inherent inertia of rotating flywheels. Progressive exercise protocols (increased frequency and magnetic force) assessed peak oxygen uptake and heart rate, rate of perceived exertion and post lactate concentration. Results Peak oxygen uptake averaged 3.18±0.50 and 3.11±0.49 l/min, respectively during exercise using CII and FWD. Peak oxygen uptake, plasma lactate concentration, heart rate and rate of perceived exertion were not different (p>0.05) across exercise using these two devices. However, time to exhaustion was somewhat (p<0.05) longer for the FWD. Conclusion: Collectively the current results suggest that the novel method of offering an aerobic exercise stimulus is as effective as the most established technology for indoor rowing used by crew. Given that the space agencies have recognized the need for effective exercise countermeasures hardware that has a feasible mass and envelope and features allowing for multiple purposes (e.g., concentric/eccentric resistance and aerobic exercise) in a single piece of apparatus, the current technology should be considered for use in space.

  • 29.
    Tesch, Per
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences. Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    Pozzo, M.
    Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    Ainegren, Mats
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Quality Technology and Management, Mechanical Engineering and Mathematics.
    Swarén, Mikael
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences.
    Linnehan, R. M.
    Astronaut Office, National Aeronautics and Space Administration, Johnson Space Center, Houston, TX, United States .
    Cardiovascular responses to rowing on a novel ergometer designed for both resistance and aerobic training in space2013In: Aviation, Space and Environmental Medicine, ISSN 0095-6562, E-ISSN 1943-4448, Vol. 84, no 5, p. 516-521Article in journal (Refereed)
    Abstract [en]

    Background: Astronauts are required to perform both resistance and aerobic exercise while in orbit. This study assessed the aerobic energy yield and related physiological measurements using a nongravity dependent flywheel device designed for both resistance and aerobic exercise (RAD) in space. Methods: Eight physically active men and women performed all-out rowing on the RAD. For comparison, exercise was also carried out employing a commercially available rowing ergometer (C2). Results: Peak oxygen uptake during exercise using RAD and C2 averaged 3.11 ± 0.49 and 3.18 ± 0.50 L · min-1 respectively. Similarly, peak plasma lactate concentration (9.6 vs. 11.2 mmol · L-1), heart rate (183 vs. 184 bpm), and rate of perceived exertion (15.8 vs. 16.0) were comparable across exercise using the two devices. Discussion: Collectively, the results suggest that this novel exercise modality offers cardiovascular and metabolic responses, and thus aerobic exercise stimulus that is equally effective as that evoked by established technology for indoor rowing. Given the need for physiologically sound and highly effective exercise countermeasures that features small mass and envelope, and allows for resistance and aerobic exercise in a single apparatus, we believe this novel hardware should be considered for use in space. © by the Aerospace Medical Association, Alexandria, VA.

1 - 29 of 29
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf