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- Hein, Tobias, 1982, et al.
(författare)
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Can minimal running shoes imitate barefoot heel-toe running patterns? A comparison of lower leg kinematics
- 2014
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Ingår i: Journal of Sport and Health Science. - : Elsevier BV. - 2095-2546. ; 3:2, s. 67-73
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Tidskriftsartikel (refereegranskat)abstract
- Background: Numerous studies about the interaction between footwear (and barefoot) and kinematic and kinetic outcomes have been published over the last few years. Recent studies however lead to the conclusion that the assumed interactions depend mainly on the subjects' experience of barefoot (BF) walking/running, the preferred running strike pattern, the speed, the hardness of the surface, the thickness of the midsole material, and the runners' level of ability. The aim of the present study was to investigate lower leg kinematics of BF running and running in minimal running shoes (MRS) to assess comparability of BF kinematics in both conditions. To systematically compare both conditions we monitored the influencing variables described above in our measurement setup. We hypothesized that running in MRS does not alter lower leg kinematics compared to BF running. Methods: Thirty-seven subjects, injury-free and active in sports, ran BF on an EVA foam runway, and also ran shod wearing Nike Free 3.0 on a tartan indoor track. Lower-leg 3D kinematics was measured to quantify rearfoot and ankle movements. Skin markers were used in both shod and BF running. Results: All runners revealed rearfoot strike pattern when running barefoot. Differences between BF and MRS running occurred particularly during the initial stance phase of running, both in the sagittal and the frontal planes. BF running revealed a flatter foot placement, a more plantar flexed ankle joint and less inverted rearfoot at touchdown compared to MRS running. Conclusion: BF running does not change the landing automatically to forefoot running, especially after a systematic exclusion of surface and other influencing factors. The Nike Free 3.0 mimics some BF features. Nevertheless, changes in design of the Nike Free should be considered in order to mimic BF movement even more closely. Copyright (C) 2014, Shanghai University of Sport. Production and hosting by Elsevier B. V. All rights reserved.
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| 2. |
- Hein, Tobias, 1982, et al.
(författare)
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Prospective analysis of intrinsic and extrinsic risk factors on the development of Achilles tendon pain in runners
- 2014
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Ingår i: Scandinavian Journal of Medicine & Science in Sports. - : Wiley. - 0905-7188 .- 1600-0838. ; 24:3
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Tidskriftsartikel (refereegranskat)abstract
- There are currently no generally accepted, consistent results that clearly characterize factors causing Achilles tendon pain (AT) in runners. Therefore, we carried out a prospective study to evaluate the multifactorial influence of clinical, biomechanical (isometric strength measurements and three-dimensional kinematics) and training-related risk factors on the development of AT. Two hundred sixty-nine uninjured runners were recruited and underwent an initial examination. One hundred forty-two subjects completed their participation by submitting training information on a weekly basis over a maximal period of 1 year. Forty-five subjects developed an overuse injury, with 10 runners suffering from AT. In an uninjured state, AT runners already demonstrated decreased knee flexor strength and abnormal lower leg kinematics (sagittal knee and ankle joint) compared with a matched control group. A relationship between years of running experience or previous overuse injuries and the development of new symptoms could not be established. The interrelationship of biomechanical and training-specific variables on the generation of AT is evident. A combination of alterations in lower leg kinematics and higher impacts caused by fast training sessions might lead to excessive stress on the Achilles tendon during weight bearing and thus to AT in recreational runners.
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| 3. |
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| 4. |
- Jungmalm, Jonatan, 1991, et al.
(författare)
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Associations between biomechanical and clinical/anthropometrical factors and running-related injuries among recreational runners: a 52-week prospective cohort study.
- 2020
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Ingår i: Injury epidemiology. - : Springer Science and Business Media LLC. - 2197-1714. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this exploratory study was to investigate whether runners with certain biomechanical or clinical/anthropometrical characteristics sustain more running-related injuries than runners with other biomechanical or clinical/anthropometrical characteristics.The study was designed as a prospective cohort with 52-weeks follow-up. A total of 224 injury-free, recreational runners were recruited from the Gothenburg Half Marathon and tested at baseline. The primary exposure variables were biomechanical and clinical/anthropometrical measures, including strength, lower extremity kinematics, joint range of motion, muscle flexibility, and trigger points. The primary outcome measure was any running-related injury diagnosed by a medical practitioner. Cumulative risk difference was used as measure of association. A shared frailty approach was used with legs as the unit of interest. A total of 448 legs were included in the analyses.The cumulative injury incidence proportion for legs was 29.0% (95%CI=24.0%; 34.8%). A few biomechanical and clinical/anthropometrical factors influence the number of running-related injuries sustained in recreational runners. Runners with a late timing of maximal eversion sustained 20.7% (95%CI=1.3; 40.0) more injuries, and runners with weak abductors in relation to adductors sustained 17.3% (95%CI=0.8; 33.7) more injuries, compared with the corresponding reference group.More injuries are likely to occur in runners with late timing of maximal eversion or weak hip abductors in relation to hip adductors.
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| 5. |
- Koska, Daniel, 1986, et al.
(författare)
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Validation of an inertial measurement unit for the quantification of rearfoot kinematics during running
- 2018
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Ingår i: Gait & Posture. - : Elsevier BV. - 0966-6362. ; 64, s. 135-140
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Tidskriftsartikel (refereegranskat)abstract
- Background: The popular protocol used to study running motion suffers from problems that lead to a limited ability to generalize the obtained results. Inertial measurement units (IMU) appear to be promising in increasing ecological validity of the collected data. However, quantifying running kinematics utilizing IMU signals is complex and potentially affected by several well-established and less well-known errors. Research question: The purpose of this study was to examine the validity of kinematic variables obtained from a single, shoe-mounted IMU using an opto-electronic motion analysis reference system. Methods: 51 recreational runners were analyzed, performing a single continuous run at three different speeds (10, 12, 15 km/h) on a treadmill. Descriptive statistics (Bland & Altman analysis, box plots, scatter plots) were employed to analyze the agreement between the two instruments. Results: The findings of this study revealed considerable systematic and large random disagreement, which, in turn, is characterized by substantial inter-individual differences in the error distribution. These discrepancies may partly be explained by differences in foot strike behavior, resulting in varying degrees of vibration impact acting on the IMU. Significance: Advances in IMU technology, as well as exploring new application approaches and signal processing strategies, might enhance the usability of IMUs in analyzing running kinematics.
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| 6. |
- Lundby, Carsten, et al.
(författare)
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Physiological, biochemical, anthropometric, and biomechanical influences on exercise economy in humans
- 2017
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Ingår i: Scandinavian Journal of Medicine & Science in Sports. - : Wiley. - 0905-7188. ; 27:12, s. 1627-1637
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Tidskriftsartikel (refereegranskat)abstract
- Interindividual variation in running and cycling exercise economy (EE) remains unexplained although studied for more than a century. This study is the first to comprehensively evaluate the importance of biochemical, structural, physiological, anthropometric, and biomechanical influences on running and cycling EE within a single study. In 22 healthy males (VO(2)max range 45.5-72.1mLmin-1kg-1), no factor related to skeletal muscle structure (% slow-twitch fiber content, number of capillaries per fiber), mitochondrial properties (volume density, oxidative capacity, or mitochondrial efficiency), or protein content (UCP3 and MFN2 expression) explained variation in cycling and running EE among subjects. In contrast, biomechanical variables related to vertical displacement correlated well with running EE, but were not significant when taking body weight into account. Thus, running EE and body weight were correlated (R-2=.94; P<.001), but was lower for cycling EE (R-2=.23; P<.023). To separate biomechanical determinants of running EE, we contrasted individual running and cycling EE considering that during cycle ergometer exercise, the biomechanical influence on EE would be small because of the fixed movement pattern. Differences in cycling and running exercise protocols, for example, related to biomechanics, play however only a secondary role in determining EE. There was no evidence for an impact of structural or functional skeletal muscle variables on EE. Body weight was the main determinant of EE explaining 94% of variance in running EE, although more than 50% of the variability of cycling EE remains unexplained.
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| 7. |
- Perchthaler, Dennis, et al.
(författare)
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Acute Effects of Whole-Body Vibration on Trunk and Neck Muscle Activity in Consideration of Different Vibration Loads
- 2015
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Ingår i: Journal of Sports Science and Medicine. - 1303-2968. ; 14:1, s. 155-162
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Tidskriftsartikel (refereegranskat)abstract
- The intention of this study was to systematically analyze the impact of biomechanical parameters in terms of different peakto- peak displacements and knee angles on trunk and neck muscle activity during whole-body vibration (WBV). 28 healthy men and women (age 23 ± 3 years) performed four static squat positions (2 peak-to-peak displacements x 2 knee angles) on a side alternating vibration platform with and without vibration stimulus. Surface electromyography (EMG) was used to record the neuromuscular activity of the erector spinae muscle, the rectus abdominis muscle, and of the splenius muscle. EMG levels normalized to maximal voluntary contractions ranged between 3.2 – 27.2 % MVC during WBV. The increase in muscle activity caused by WBV was significant, particularly for the back muscles, which was up to 19.0 % MVC. The impact of the factor ‘condition’ (F-values ranged from 13.4 to 132.0, p ≤ 0.001) and of the factor ‘peak-to-peak displacement’ (F-values ranged from 6.4 to 69.0 and p-values from < 0.001 to 0.01) were statistically significant for each muscle tested. However, the factor ‘knee angle’ only affected the back muscles (F-value 10.3 and 7.3, p ≤ 0.01). The results of this study should give more information for developing effective and safe training protocols for WBV treatment of the upper body.
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| 8. |
- Perchthaler, Dennis, et al.
(författare)
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Evaluation of a six-week whole-body vibration intervention on neuromuscular performance in older adults
- 2015
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Ingår i: Journal of Strength and Conditioning Research. - 1064-8011. ; 29:1
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Forskningsöversikt (refereegranskat)abstract
- Perchthaler, D, Grau, S, and Hein, T. Evaluation of a 6-week whole-body vibration intervention on neuromuscular performance in older adults. J Strength Cond Res 29(1): 86–95, 2015—Research in the field of whole-body vibration (WBV) for the enhancement of neuromuscular performance is becoming increasingly popular. However, additional understanding of optimal WBV training protocols is still necessary to develop optimal and effective training and prevention concepts, especially for elderly people. The intention of this study was to evaluate a 6-week WBV intervention program based on optimal vibration loads adapted from the literature on lower-limb strength parameters and performance, as well as on perceived exertion according to a subjective rating. A total of 21 older adults were allocated randomly into either a WBV training or control group (CO). Before and after the intervention period, jump height was measured during a countermovement jump. In addition, isolated isokinetic maximal knee extension and flexion strength, mean power, and work were recorded using a motordriven dynamometer. Borg’s scale for rating of perceived exertion was used to evaluate the intensity of WBV exercises within each training session. After the intervention period, jump height increased by 18.55% (p , 0.001) in the WBV group, whereas values of the CO remained unchanged. There were no statistically significant differences in isokinetic maximal strength, mean power, or work values in knee extension or flexion (all p . 0.05). Finally, the subjective perceived exertion of the WBV exercises and respective training parameters ranged between moderate rating levels of 7 and 13 of Borg’s scale. Our data show that WBV is a feasible and safe training program for elderly people to increase multijoint strength performance of the lower limbs during a countermovement jump. This could help to determine the potential of WBV programs in training of the elderly to prevent age-related reduction of neuromuscular performance.
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| 9. |
- Syha, R., et al.
(författare)
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Computer-based quantification of the Achilles tendon thickness in sequential B-mode ultrasound images: a study of feasibility and reliability
- 2014
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Ingår i: Archives of Orthopaedic and Trauma Surgery. - : Springer Science and Business Media LLC. - 0936-8051 .- 1434-3916. ; 134:10, s. 1443-1449
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Tidskriftsartikel (refereegranskat)abstract
- Assessment of the Achilles tendon thickness (ATT) using B-mode ultrasound is a common technique for clinical evaluation of chronic mid-part tendinosis. Currently used image-based assessment is limited by relatively high inter- and intra-observer variability. In this study, it was tested whether a new sequence-based automated assessment of ATT provides more reliable and reproducible results than the standard image-based procedure. A total of 118 non-operated tendons of 59 healthy subjects (44, range 28-50 years) were analysed using an automated image based as well as a newly developed automated sequence-based method. Correlation and agreement of both methods were evaluated. The root mean square deviation (RMSD) and a Bland-Altman analysis were performed to highlight observer (n = 18 tendons) as well as reader (n = 40 tendons) dependent variabilities of both methods. A strong correlation was found between image and sequence-based ATT assessment (p = 0.92). The Bland-Altman analysis showed a good agreement between both methods (mean difference 0.0018, 95 % CI: -0.046; 0.05). In repetitive examinations, sequence-based analysis showed a significant reduction concerning reader- and observer-dependent variability compared to image-based assessment. The RMSD for repetitive sequence-based measurements was approximately 0.3 mm (compared to 0.6 mm for image-based measurement), respectively. The study shows sequence-based automated assessment of ATT being clearly superior to the standard image-based procedure. The new method provides a clear reduction of reader as well as observer-dependent variability. Due to the decreased scattering of measurement data sequence-based measurement seems especially valuable for quantification of small tendon thickness changes such as exercise-induced hypertrophy.
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