Browsing by Author "Janura, Miroslav"
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- ItemComparison of foot loading and foot strike pattern in women running in minimalist and conventional sports shoes(UNIV PALACKEHO & OLOMOUCI, FAK TELESNE KULTURY, TR MIRU 115, OLOMOUC, 77111, CZECH REPUBLIC, 2019) Jandová, Soňa; Charousek, Jan; Janura, MiroslavBackground: At present, most runners use conventional sports shoes to protect and absorb the impacts that may cause overloading of the feet and joints. On the other hand, some runners tend to run almost barefoot or in minimalist footwear that may lead to foot strike pattern changes. Objective: The aim of this study was to analyse and to compare the foot strike pattern and foot loading when running in conventional running shoes (CRS) and minimalist running shoes (MRS) in a group of recreational women runners. Methods: A group of 14 experienced recreational women runners participated in this research. A Pedar-X system (Novel, Munich, Germany) was used to analyse the interaction of the foot with the ground while running in different type of shoes from as it relates to vertical force and plantar pressure distribution. The participants ran over a distance of 100 m with their habitual foot strike pattern in minimalist and also in conventional running shoes and data was always obtained while running along a straight 50 m long section (v = 3.33 +/- 0.2 m.s(-1)). For assessment of the temporal and kinetics variables differences, the Wilcoxon test and the unpaired t-tests were used. Results: Recreational women runners showed statistically significant shift of the plantar pressures towards the forefoot when running in MRS compared to CRS (p = .047). Duration of swing phase in MRS and in CRS was similar (p = .291). When running in MRS, foot loading during initial contact was significantly higher than when running in CRS. Loading in the area of midfoot and forefoot was significantly higher in MRS too. Conclusions: Runners shifted their foot strike pattern forward when running in MRS; running in MRS may increase the foot loading and we recommend the use of minimalist footwear only after adequate foot strengthening and adaptation to avoid possible risk of foot injuries.
- ItemComparison of Plantar Pressure Distribution During Walking After Two Different Surgical Treatments for Calcaneal Fracture(2019-03) Jandová, Soňa; Pazour, Jan; Janura, MiroslavThe aim of our study was to compare gait in terms of foot loading and temporal variables after 2 different operative approaches (the extended lateral approach [ELA] and sinus tarsi approach). Twenty-two patients who sustained an intra-articular calcaneal fracture underwent plantar pressure distribution measurements 6 months after surgery. Measurements were performed while patients walked on the pedobarography platform. The values of dynamic variables were significantly lower on the operated limb in the ELA. In the sinus tarsi approach, no differences were observed between the operated and uninjured limbs (UIN) at peak pressure and at maximal vertical force. The values of temporal variables (contact time of the foot and of the heel) between the operated and UIN differed in the ELA. The hypothesis that differences in foot load between operated and UIN will be more significant in the ELA was confirmed. Our results showed that the differences in loading and temporal variables between the operated and the UIN persisted 6 months after surgery in both methods. The operated limb was less loaded, with the tendency to shift the load toward the midfoot and forefoot. After the less invasive sinus tarsi approach, the dynamic and temporal variables on the operated limb were nearly the same as those on the healthy one. The sinus tarsi surgical approach can be recommended for treatment of displaced calcaneal fractures.
- ItemJumping performance and take-off efficiency in two different age categories of female volleyball players(WROCLAW UNIV TECHNOLOGY, FAC COMPUTER SCIENCE & MANAGEMENT, WYBRZEZE WYSPIANSKIEGO 27, WROCLAW, 50-370, POLAND, 2019) Jandová, Soňa; Janura, MiroslavPurpose: Vertical jump height is recognised as a determinant factor in elite volleyball performance. In previous studies there are different opinions on whether vertical jump height performance improves during maturation or not. The aim of this study was to assess the differences in jumping abilities in two different age groups of female volleyball players and to determine the take-off efficiency during repeated jumps. Methods: Seventeen female volleyball players from two different age categories - adults and under 16 years - participated in this study. Quattro Jump 9290BA force platform (Kistler, Winterthur, Switzerland) was used to assess the jumping performance during squat jumps, counter movement jumps, and 45-second continuous jumps. Results: Jumping performance did not differ significantly between the two groups. The main efficiency of the conversion of mechanical work into mechanical energy was only 24% and it decreased during the test. Conclusions: The influence of age on the jumping performance in a group of female volleyball players was not confirmed. Take-off efficiency was in both groups quite low and it did not improve during the test.
- ItemStanding balance of professional ballet dancers and non-dancers under different conditions(PUBLIC LIBRARY SCIENCE, 1160 BATTERY STREET, STE 100, SAN FRANCISCO, CA 94111 USA, 2019-10-22) Janura, Miroslav; Procházková, Markéta; Svoboda, Zdeněk; Bizovská, Lucia; Jandová, Soňa; Konečný, PetrBallet training has been reported to positively influence balance ability. It is not entirely clear how improved balance ability manifests under standing conditions with different demands on postural control. The aim of the study was to compare balance of ballet dancers and nondancers in a unipedal stance under different conditions. Twenty-five professional ballet dancers and twenty-five controls completed four unipedal standing balance tests: firm surface with eyes open and closed; foam mat surface with eyes open; and firm surface with eyes open immediately after performing ten 360 degrees whole-body turns. The centre of pressure (COP) data were obtained with a force platform and the direction-specific standard deviations, velocities, and sample entropy of the COP displacement were computed. A three-way analysis of variance was used to compare groups, genders, and conditions. For standing immediately after performing ten turns, the postural sway parameters were significantly larger in the control group compared to the ballet dancers in both men and women. In this stance condition the values of postural sway and COP velocities in the control group were larger in the men compared to the women. For both genders in the control group all postural sway and COP velocity parameters were larger in standing with eyes closed and standing after performing 10 turns compared to standing with eyes open on both firm and foam surface. In the ballet dancers all COP velocity parameters were larger in standing with eyes closed compared to all other conditions. The results from the present study indicate that professional ballet dancers do not have a better general balance ability than untrained subjects.