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Reference values of spatiotemporal parameters, joint angles, ground reaction forces, and plantar pressure distribution during normal gait in young women

Fryzowicz A., Murawa M., Kabaciński J., Rzepnicka A., Dworak L. B.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 1

49--57

EN

The aim of this study was to establish the reference values of spatiotemporal parameters, joint angles, ground reaction forces and plantar pressure distribution collected simultaneously on the same measurement path during normal gait in a homogenous group of young, healthy women. Methods: The studied group consisted of 28 healthy women aged 21 years on average. The motion capture system BTS Smart-D, 2 AMTI force platforms and Footscan pedobarographic platform were used in this research. The 14-metre measurement path and the 6-metre distance that examined women had to walk through before entering the measurement area ensured that a natural gait pattern was recorded. Statistical analysis was performed to evaluate differences between right and left lower extremities. Results: The applied method enabled collecting several parameters regarding normal female gait biomechanics such as: spatiotemporal parameters, angle-time characteristics as well as range of motion of pelvis, hip, knee and ankle joints in gait cycle, force-time characteristics and peaks of ground reaction force components in stance phase, peak pressure and time of loading of defined foot regions in stance phase. Conclusions: The results may be used by clinicians, physiotherapists or researchers as a reference in diagnosing gait disorders or evaluating patient’s walking pattern. In recent literature there are some disparities in gait parameters reference values even regarding similar research groups. These differences may arise from distinct method, slower or faster gait, other laboratory environment etc. This should be considered and more than one source of normative values should be checked when searching for reference data.

2

Izokinetyczna ocena ekscentrycznej siły mięśni grupy tylnej i przedniej uda siatkarzy

Kabaciński J., Murawa M., Żyła T., Gorwa J., Dworak L. B.

Aktualne Problemy Biomechaniki

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2017

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z. 12

35--40

PL

W pracy określono wartości wybranych wskaźników ekscentrycznej siły mięśni uda siatkarzy w warunkach izokinetycznych. Ocenie poddano stosunek momentu siły hamstrings do quadriceps (H/Q) oraz bilateralny deficyt maksymalnego momentu siły mięśni (BD) dla prędkości kątowych 30°/s, 60°/s i 90°/s. Wartości maksymalnego H/Q zawierały się od 69.0% (90°/s) do 81.3% (30°/s), natomiast średniego H/Q od 68.6% (90°/s) do 78.7% (30°/s). Ponadto, stwierdzono nieistotny BD (poniżej 7%) dla obu zespołów mięśniowych.

EN

In the study the values of selected indicators of thigh eccentric isokinetic strength in volleyball athletes at angular velocities 30°/s, 60°/s and 90°/s was determined. The evaluation included the hamstrings to quadriceps torque ratio (H/Q) and peak torque bilateral deficit (BD). The peak H/Q values ranged from 69.0% (90°/s) to 81.3% (30°/s), whereas average H/Q values ranged from 68.6% (90°/s) to 78.7% (30°/s). Moreover, no significant BD values (less than 7%) were found for both muscle groups.

3

Dynamic parameters of three-point crutch gait in female patients after total hip arthroplasty

Murawa M., Dworak L. B., Kabaciński J., Syczewska M., Rzepnicka A.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 2

131--135

EN

Purpose: Patient recovery after a surgical procedure depends, among other factors, on the amount of the body weight with which patient loads lower limb. Research studies report different results of the degree of body weight with which lower limb is loaded during three-point crutch gait. The aim of this study was to evaluate the level of the ground reaction forces (GRF) during crutch gait used by patients after total hip arthroplasty (THA) in the first week after discharge from the orthopaedic units. Methods: Ten female patients diagnosed with primary unilateral coxarthrosis participated in a single measurement session. In order to record kinematic and dynamic variables of this gait pattern motion analysis system was used together with two force plates. The static test of body weight distribution between lower limbs was performed on a dual-top stabilometric plate. Results: The average peak values of loading on the operated (O) limb during mid stance and terminal stance of three-point crutch gait were 64.6% and 64.3% of body weight (BW), respectively, whereas in the case of the nonoperated (NO) limb 103.5%BW and 108.8%BW, respectively. The maximum loads on the crutches were significantly higher (by 9%BW) on the NO side as compared to the O side ( p < 0.05). During the static test, average values of body weight distribution on the O and NO limb were 36%BW and 64%BW, respectively. Conclusions: The patients showed surprisingly similar level of loading on the O limb. The weight bearing on the O limb was lower during static trial than during three-point crutch gait.

4

Dynamic load indicators for take-off–landing sequence in blocks and attacks of elite female volleyball players

Kabaciński J., Dworak L. B., Murawa M., Rzepnicka A.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 1

41--46

EN

Purpose: Dynamic loads during landings determined by the ground reaction forces (GRFs) may elaborate internal loads and increase the risk of overload knee injuries as a result of performing volleyball jumps many times. The study dealt with a biomechanical assessment of dynamic load indicators in female volleyball players for the motion sequence of take-off–landing in blocks and attacks. Methods: Twelve professional female volleyball players participated in the study. Blocks and attacks were filmed by two cameras. GRFs vs. time graphs were recorded with the use of a force platform. Values of dynamic load indicators in terms of the relations of peak of vertical component of GRF, build-up index of this force (BIF), and power output (P) during landing to the vGRF, BIF and P during take-off (L/T) were calculated. Results: The statistically significant ( p < 0.05) highest values of L/T indicators were found for back row attack spikes: 2.4 (vGRF), 12.2 (BIF) and 3.1 (P). In the case of blocks, slide attack spikes and attack line spikes, results of these variables were in range: 1.8÷2.1, 5.9÷7.6 and 2.1÷2.9, respectively. Conclusions: The reduction of GRFs during landings contributes to decreasing the level of the load indicators L/T which should minimize the incidence of anterior cruciate ligament and patellar tendon injuries in female volleyball players.

5

Sports biomechanics in the research of the Department of Biomechanics of University School of Physical Education in Poznań. Part 1 Biomechanics of rowing: tests on rowing ergometers, reconstruction and synthesis

Dworak L. B.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 1

55-64

EN

The purpose of this study is to reconstruct the early phase of scientific research conducted at the Department of Biomechanics of the University School of Physical Education in Poznań, particularly the work on biomechanics of rowing, conducted as part of the Ministerial Project PR 105, entitled “The effectiveness of training and competition as well as regeneration in sports”. Three kinds of research have been described, carried out with the use of the rowing ergometers. The first was the research on neuromuscular coordination in the rowing cycle, the second was the research on kinematic and dynamic characteristics of rowing on the Universal Rowing Ergometer UEW-1, while the last one concerned determination of maximum forces generated by functional muscle groups in two characteristic rowing positions within the closed biochain of the torso and the limbs.

6

Sports biomechanics in the research of the Department of Biomechanics of University School of Physical Education in Poznań. Part 2 Biomechanics of rowing: research conducted in the rowing pool and under real conditions. Reconstruction and synthesis

Dworak L. B.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 3

103-112

EN

The purpose of this study was to reconstruct the early phase of scientific research conducted at the Department of Biomechanics of the College of Physical Education and since 1972 at the University School of Physical Education in Poznań, with special attention paid to the works on biomechanics of rowing, carried out as part of the Ministerial Project PR 105 entitled The effectiveness of training, sports competition as well as regeneration in sports. Two kinds of biomechanical research are described: the several years’ expert research conducted on the Rowing National Team in an original two-module Rowing Pool Testing Station BTW-1, as well as research on geometric optimization of the rowing station, conducted under real conditions, in reservoirs, with the use of a prototypical, unique at that time, computer measurement system BIOMIK, installed in the rower’s own boat. The projects were carried out by doctoral students from the Department of Biomechanics and the Department of Clinical Biomechanics, Andrzej Lisiecki and Wojciech Mikołajczyk, respectively.

7

AVIImage – video motion analysis software for tests of biomechanical movement characteristics

Rostkowska E., Benz P., Dworak L. B.

Acta of Bioengineering and Biomechanics

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2006

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Vol. 8, nr 1

91-102

EN

The aim of this paper is to introduce our AVIImage software for the analysis of movement technique recorded by means of video registration with RGB 24 bits depth. AVIImage software allows manual or automatic recognition of markers characterising the object examined, analysis of basic parameters in 2D or 3D of kinematic structure of movement.

8

Dynamic loads in some movement structures in acrobatics. A preliminary study

Dworak L. B., Twardowska M., Wojtkowiak T., Kmiecik K., Mączyński J.

Acta of Bioengineering and Biomechanics

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2005

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Vol. 7, nr 1

69-75

EN

The aim of the paper was identification of force-time characteristics of ground reaction forces exerted during take-off and landing phases in the six typical acrobatic elements. The tests of a pilot study character were carried out on two professional athletes aged 17 and I8. The levels of such parameters characterizing dynamic loads and overloads of examined movement structures as: maximal and average values of vertical ground reaction forces, total time of support phases, time necessary for generation of maximal force, force buildup indexes as well as force impulses were calculated. The results obtained suggest that dynamic overloads are serious and of traumatic character.

9

A study characterizing dynamic overloads of professional dancers. Biomechanical approach

Dworak L. B., Gorwa J., Kmiecik K., Mączyński J.

Acta of Bioengineering and Biomechanics

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2005

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Vol. 7, nr 1

77-84

EN

Many jumps made in classical and modem ballet are responsible for serious injuries. A pilot experiment that was earned out with two professional dancers measured the temporary character of ground reaction forces in a few chosen elements of classical dance. The method of piezoelectric dynamometry as well as video recording were applied. The results of the experiment concerning the dynamic overloads, which are defined by the value of ground reaction forces, allow us to set the direction of a further research in the area of biomechanical interpretations.

10

Gait in subjects with hemiplegia

Karsznia A., Oberg T., Dworak L.B.

Acta of Bioengineering and Biomechanics

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2004

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Vol. 6, nr 2

65-76

EN

The gait of 39 patients, 24 men and 15 women, was evaluated. The mean time from the stroke to examination was 17.4 months. Basic gait parameters, joint angle parameters and ground reaction forces (i.e. both kinematic and kinetic data) were evaluated in a gait laboratory on a 10m walkway with two paral-lell, 5 m long force platforms. The recorded parameters represent the mean of 20-30 steps for each patient. Our results show quite a complete picture of hemiparetic gait: a reduction of all the basic gait parameters; a reduction of joint excursions in the hip and knee on both sides, significantly more on the affected side; only minor reduction of the vertical ground reaction forces, with no side differences; a reduction of the horizontal retardation and acceleration forces; and a reduced reproducibility of gait in angle-angle diagrams, indicating coordination problems. There were no major sex differences. Basic gait parameters were improved with time after the onset after the stroke. We found significant changes of gait parameters not only on the paretic side, but on the non-paretic side as well. We could not verify the stiff-knee walking pattern described earlier in the literature; and we found no weight take-over on the paretic side. These findings may be important in the design of training programs for stroke patients. They also show the importance of objective evaluation of gait after stroke.

11

Dynamic overloads during marching past gait

Dworak L. B., Kmiecik K., Mączyński J.

Acta of Bioengineering and Biomechanics

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2000

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Vol. 2, nr 1

71-75

EN

The paper presents quantities which characterise overloads during marching past gait obtained from the time curves of the ground reaction forces. The following quantities were interpreted: time of single support, time of strike, extreme values of ground reaction force in the sagittal plane, build-up force indexes and velocity of marching past gait.