| 1. |
- Gilenstam, Kajsa M., 1974-, et al.
(författare)
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Physiological Correlates of Skating Performance in Women's and Men's Ice Hockey
- 2011
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Ingår i: Journal of Strength and Conditioning Research. - : National Strength and Conditioning Association. - 1064-8011 .- 1533-4287. ; 25:8, s. 2133-2142
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the current investigation was to identify relationships between physiological off-ice tests and on-ice performance in female and male ice hockey players on a comparable competitive level. Eleven women, 24 ± 3.0 years, and 10 male ice hockey players, 23 ± 2.4 years, were tested for background variables: height, body weight (BW), ice hockey history, and lean body mass (LBM) and peak torque (PT) of the thigh muscles, [latin capital V with dot above]o2peak and aerobic performance (Onset of Blood Lactate Accumulation [OBLA], respiratory exchange ratio [RER1]) during an incremental bicycle ergometer test. Four different on-ice tests were used to measure ice skating performance. For women, skating time was positively correlated (p < 0.05) to BW and negatively correlated to LBM%, PT/BW, OBLA, RER 1, and [latin capital V with dot above]o2peak (ml O2·kg-1 BW-1·min-1) in the Speed test. Acceleration test was positively correlated to BW and negatively correlated to OBLA and RER 1. For men, correlation analysis revealed only 1 significant correlation where skating time was positively correlated to [latin capital V with dot above]o2peak (L O2·min-1) in the Acceleration test. The male group had significantly higher physiological test values in all variables (absolute and relative to BW) but not in relation to LBM. Selected off-ice tests predict skating performance for women but not for men. The group of women was significantly smaller and had a lower physiological performance than the group of men and were slower in the on-ice performance tests. However, gender differences in off-ice variables were reduced or disappeared when values were related to LBM, indicating a similar capacity of producing strength and aerobic power in female and male hockey players. Skating performance in female hockey players may be improved by increasing thigh muscle strength, oxygen uptake, and relative muscle mass.
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| 2. |
- Gustafsson, Henrik, et al.
(författare)
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Athlete burnout : an integrated model and future research directions
- 2011
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Ingår i: International Review of Sport and Exercise Psychology. - : Routledge Taylor and Francis Group. - 1750-984X .- 1750-9858. ; 4:1, s. 3-24
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Tidskriftsartikel (refereegranskat)abstract
- Athlete burnout is a multifaceted phenomenon. As a consequence, several attempts have been made to describe it from both a process and a state perspective. A number of theories and models exist that deal with the process of burning out and/or its antecedents. When viewed separately, the presented findings may be perceived as contradicting each other, or at best as confusing. To advance the field, we offer a comprehensive review of what is presently known within the area of athlete burnout and what new knowledge is needed. Furthermore, we suggest an integrated model of athlete burnout. This model includes major antecedents, early signs, consequences, and factors related to personality, coping and the environment. Our purpose is not to present the definitive model but to create a conceptual understanding of the field as it is seen today, and thereby stimulate empirical research to further advance the knowledge base.
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| 3. |
- Malm, Christer, et al.
(författare)
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Immunological Alterations Used to Predict Infections in Response to Strenuous Physical Training
- 2011
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Ingår i: Military medicine. - : AMSUS - Association of Military Surgeons of the U.S.. - 0026-4075 .- 1930-613X. ; 176:7, s. 785-790
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT The aim of this study was to screen leukocyte cell surface markers to identify possible predictors for infection related to physical training. Ten healthy soldiers (mean age, 19.1; mean body mass, 77.4 kg; mean VO ^sub 2^ peak, 4.54 L min ^sup -1^ /58.6 mL min ^sup -1^ kg ^sup -1^ ) were included. Blood samples were collected and number of infections recorded before and after a 6-day training course. White blood cell distributions and expression of surface receptors changed during training. Before training, expression of CD3 on CD8 lymphocytes and percent CD8 CD3 lymphocytes was lower, whereas CD4/CD8 ratio was higher among subjects who failed compared to those who completed the training. A subclinical infection before the start of the military training may alter the CD4/CD8 ratio. Prediction of future infections may be possible from pre-exercise immunological status, fi ndings useful in military settings and exercise, where sudden infections may result in severe consequences.
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| 4. |
- Peolsson, Michael, et al.
(författare)
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Modelling human musculoskeletal functional movements using ultrasound imaging
- 2010
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Ingår i: BMC Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 10, s. 9-
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Tidskriftsartikel (refereegranskat)abstract
- Background: A widespread and fundamental assumption in the health sciences is that muscle functions are related to a wide variety of conditions, for example pain, ischemic and neurological disorder, exercise and injury. It is therefore highly desirable to study musculoskeletal contributions in clinical applications such as the treatment of muscle injuries, post-surgery evaluations, monitoring of progressive degeneration in neuromuscular disorders, and so on.The spatial image resolution in ultrasound systems has improved tremendously in the last few years and nowadays provides detailed information about tissue characteristics. It is now possible to study skeletal muscles in real-time during activity.Methods: The ultrasound images are transformed to be congruent and are effectively compressed and stacked in order to be analysed with multivariate techniques. The method is applied to a relevant clinical orthopaedic research field, namely to describe the dynamics in the Achilles tendon and the calf during real-time movements.Results: This study introduces a novel method to medical applications that can be used to examine ultrasound image sequences and to detect, visualise and quantify skeletal muscle dynamics and functions.Conclusions: This new objective method is a powerful tool to use when visualising tissue activity and dynamics of musculoskeletal ultrasound registrations.
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| 5. |
- Wichardt, Emma, et al.
(författare)
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Rhabdomyolysis/myoglobinemia and NSAID during 48-hours ultra-endurance exercise (adventure racing)
- 2011
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 111:7, s. 1541-1544
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To determine if rhabdomyolysis with myoglobinemia exists during a 48+ hour adventure race and if there is a correlation with NSAID use, race time and perceived pain or exertion. Method: Blood samples for analyses of myoglobin (Mb) were collected, and perception of exertion and pain registered on the Borg-RPE and CR scales, from 20 subjects (3 female, 17 male) Pre, Mid and Post race. Subjects were asked about NSAID use at each sampling and within 12 hours pre race. Result: A significant rise in Mb was observed throughout the race, with the NSAID group (n=6) having significantly lower Mb-Post than the no-NSAID group (n=14). High Mb-Pre and Post correlated to shorter race time and high Mb-Pre to lower Pain-Post. Race time also correlated to NSAID use, with the NSAID group having significantly longer race time than the no-NSAID group. Conclusion: Rhabdomyolysis with myoglobinemia, which might be reduced with NSAID use, exists during a 48+ hour adventure race. Indications that high Mb-levels correlate with shorter race time and less pain, and the reasons for the NSAID groups longer race time, need further investigation.
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