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Foot mechanics in young women are altered after walking in high-heeled shoes

Winiarski S., Rutkowska-Kucharska A., Zostawa P., Uścinowicz-Zostawa N., Klich S.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 3

107--113

EN

Nowadays, fashion has caused that many young women are wearing high-heeled shoes. Therefore, the aim of this study was to examine the effects of long-term walking in high-heeled shoes on the foot mechanics during barefoot gait. Methods: Forty-three young women (22 ± 2.1 years) divided into two groups participated in this retrospective cohort study. The first group was composed of women who frequently wear high-heeled footwear. The second, infrequent wearers group, consisted of women who preferred flat-heeled shoes. Measurements of gait parameters were recorded for barefoot gait. A motion analysis system and two force plates were used in order to evaluate the lower-limb rocker mechanism, transverse foot arch height and parameters of ground reaction force. Results: Walking in high-heeled shoes modified barefoot foot mechanics, which manifested itself in a shorter duration (by ca. 4%) of the first and second rocker and a significantly longer duration (by 5%) of the third rocker phase as well as a substantial reduction in height of the transverse foot arch (by around 50%) in women habitually walking in high-heeled shoes. A significantly shorter relative duration of the third rocker (44.3% of cycle time) and greater value of the vertical component of ground reaction force (114.7% BW) in the third rocker phase were found in the group of women habitually walking in high-heeled shoes. Conclusions: The mechanism of foot rolling, with flattened foot arch, and significantly higher values of the vertical component of ground reaction force and shorter time might lead to overload in lowerlimb joints in young women.

2

Relationship between lower limbs kinematic variables and effectiveness of sprint during maximum velocity phase

Struzik A., Konieczny G., Grzesik K., Stawarz M., Winiarski S., Rokita A.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 4

131--138

EN

Purpose: The aim of the study was to determine the relationships between time of running over a 15–25 m section of a 30-meter run along a straight line and changes in the angle and angular velocity observed in ankle, knee and hip joints. Therefore, the authors attempted to answer the question of whether a technique of lower limbs movement during the phase of sprint maximum velocity significantly correlates with the time of running over this section. Methods: A group of 14 young people from the Lower Silesia Voivodeship Team participated in the experiment. A Fusion Smart Speed System was employed for running time measurements. The kinematic data were recorded using Noraxon MyoMotion system. Results: There were observed statistically significant relationships between sprint time over a section from 15 to 25 m and left hip rotation (positive) and between this time and left and right ankle joint dorsi-plantar flexion (negative). Conclusions: During the maximum velocity phase of a 30 m sprint, the effect of dorsi-plantar flexion performed in the whole range of motion was found to be beneficial. This can be attributed to the use of elastic energy released in the stride cycle. Further, hip rotation should be minimized, which makes the stride aligned more along a line of running (a straight line) instead of from side to side.

3

Symmetry of support scull and vertical position stability in synchronized swimming

Winiarski S., Dubiel-Wuchowicz K., Rutkowska-Kucharska A.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 1

113--122

EN

Maintaining the body underwater in the so-called vertical position, where the body is inverted (head down) and balanced, is made possible by performing the support scull movement by the upper limbs. In synchronized swimming, the main criteria for judging this vertical position are maintaining body stability and the maximum height of the lower limbs one is able to extend out of the water. Therefore, it seems important to examine for any correlations between the symmetry of the upper limb’s movement (sculling) and the ability to maintain balance of the body. The aim of this study was to use a dynamical asymmetry index (DAI) to assess the symmetry of the upper limb movements performed in synchronized swimming. The use of the dynamical asymmetry index is considered to be advantageous over the asymmetry coefficient, which is better known in literature on the subject and has been used by numerous authors, as it not only evaluates the magnitude of the asymmetry, but also indicates in which phases of movement asymmetry is the greatest or where it is the least significant.

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Three-dimensional human gait pattern - reference data for normal men

Pietraszewski B., Winiarski S., Jaroszczuk S.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 3

9-16

EN

The aim of this research was to establish a kinematic pattern of adult gait for motion analysis system BTS Smart-E used in the research conducted in the Laboratory of Biomechanical Analysis, University School of Physical Education, Wrocław. This research presents the results of gait patterns for a group of 17 adult males for three speed levels: high (1), preferred (2), and low (3). Subject's sex, age and speed of gait are to be considered in the kinematic normal gait pattern. No statistically significant differences were observed between the right and the left limb. However, differences between the high, preferred and low gait speed were noticeable. An increase in gait speed was related to the change in the angular range of motion in the hip, knee and ankle joints sagittal plane. The range of motion in joints mostly increased with the subjects' speed. No significant differences between the range of motion and speed were observed in the ankle joint.

5

Evaluation of gait kinematics and symmetry during the first two stages of physiotherapy after anterior cruciate ligament reconstruction

Winiarski S., Czamara A.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 2

91-100

EN

One of the primary goals of physiotherapy after anterior cruciate ligament (ACL) reconstruction is to restore of the patient's normal gait patterns. However, to date, only a limited number of studies have examined gait during physiotherapeutic procedures following ACL reconstruction. Thus, the objective of the present study was to evaluate gait kinematics and symmetry in male patients after ACL reconstruction during the first two stages of their physiotherapy programme. Ninety-seven males, including 53 patients after primary ACL reconstruction in one limb and 44 healthy controls, participated in the study. The patients were examined using a movement analysis system during their physiotherapeutic programme (from the 2nd to the 12th week following reconstruction). Some selected parameters of gait kinematics, a dynamic range of movement in the knee joint and gait asymmetry coefficients were evaluated. During the 12th week of physiotherapy, a mean gait velocity increased by more than 0.97 m/s compared to that obtained during the 2nd week of physiotherapy. A statistically significant increase in the relative length of stance phase was observed in the involved extremity, from 36.1% to 62.7% (P = 0.01); the range of movement significantly improved from 25.8 degrees during the 2nd week to 63.7 degrees during the 12th week of physiotherapy. At the same time, the stance time asymmetry coefficient decreased from 68.5% to –0.4%. We observed a significant improvement in most of the gait parameters from the 2nd to the 12th week of physiotherapy after reconstruction and also in comparison to the results obtained for the control group.

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Estimated ground reaction force in normal and pathological gait

Winiarski S., Rutkowska-Kucharska A.

Acta of Bioengineering and Biomechanics

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2009

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Vol. 11, nr 1

53-60

EN

In clinical gait analysis, ground reaction force (GRF) is the gait parameter which can validate the state of disorder of the patient's movement. The purpose of this study was to explore the possibilities of employing the GRF derived from kinematics of the center of gravity (COG) in the study of dynamics of human gait. Gait data was collected for healthy able-bodied men and women and patients after ACL reconstruction who use larger lateral COG excursions during gait. Reasonable agreement between methods was found in fore-aft and vertical directions, where the methods differed by an average of less than 10% in either direction. Based on model predictions of the body's COG trajectory during walking, algorithms were developed to determine spatio-temporal gait parameters related to GRF characteristics. The suitability of calculating ground reaction forces using COG displacement in a patient population is questioned.

7

Bioelectric activity of selected muscle groups in people with impingement syndrome

Skolimowski J., Winiarski S., Anwajler J., Skolimowska B., Barczyk K., Dudek K.

Acta of Bioengineering and Biomechanics

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2009

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Vol. 11, nr 1

38-45

EN

The aim of this study was to assess the changes of the bioelectric activity of the selected muscles and their impact on the functioning of the shoulder joint in people with impingement syndrome. The study covered 58 subjects aged between 24 and 85, who were treated for impingement syndrome in the years 2004-2006. The average duration of the disease was 40 months. The following muscles were tested for bioelectric activity using surface myography: deltoid, supraspinatus, infraspinatus, latissimus dorsi, greater pectoral and biceps brachii on the healthy and the diseased sides. A significant drop in activity of the deltoid and the infraspinatus muscles on the diseased side was observed. The following muscles showed comparable activity on both sides: the supraspinatus, latissimus dorsi and the greater pectoral muscle. The activity of the biceps brachii muscles grew during resisted movements. The drop in the activity of the deltoid and the infraspinatus muscles on the affected side is an important factor responsible for changes of the active mobility of the shoulder and for the development of instability of the shoulder joint. A similar activity of the latissimus dorsi, greater pectoral and biceps brachii muscles on both sides indicates a development of the compensatory mechanisms and the role of those muscles in the dynamic stabilisation of the shoulder joint.

8

Mechanical energy fluctuations during walking of healthyand ACL-reconstructed subjects

Winiarski S.

Acta of Bioengineering and Biomechanics

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2008

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Vol. 10, nr 2

57-63

EN

In a clinical gait analysis, mechanical energy is the gait variable which can validate the energetic state of the disorder of patient’s movement. The purpose of this study was to explore the possibilities of employing the total mechanical energy in estimating the mechanical cost of transport in normal and pathological human gait. One of the basic methods of determining mechanical energy (inverted pendulum model) was used to estimate the external mechanical work performed by the walking subjects based on externally observable measurements. Gait data was collected for healthy able-bodied men and patients after ACL reconstruction during physiotherapy process who demonstrate larger lateral center of gravity (CoG) excursions during gait. Based on predictions of the body’s CoG trajectory during walking, algorithms were developed to determine the changes in components of total mechanical energy in normal and pathological gait. The utility of calculating mechanical energy in a patient population is questioned.

9

Peak ground reaction force and loading rate from kinematics in the ACL deficient patients

Winiarski S., Siemieński A.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

377-382

EN

In clinical gait analysis ground reaction force measurement is the gait parameter which can validate the state of disorder of the patient's movement. 3D kinematic gait analysis was conducted on normal and ACL-deficient subjects to test the usefulness of ground reaction force (GRF) measurement obtained from the kinematic data of the body center of gravity (COG) in clinical condition. The 3D displacement of the COG was calculated using the Clauser model and acceleration was calculated using double differential operation. Peak force and loading rate in gait was estimated from kinematics and directly from force plate measurement.