Search

The aims of the research were to (1) determine the values of kinematic parameters in two modifications of the topspin forehand stroke as well as the differences between them and (2) assess the inter-individual and intra-individual variability of the values. Two modifications of a topspin forehand were evaluated: topspin after a topspin ball (TF1) and topspin after a backspin ball (TF2). The MyoMotion Noraxon analysis system was used to record the kinematic data. A piezo-electric sensor was used to identify the moment when the ball made contact with the racket. The coefficient of variation determined the variability of the kinematic parameters. Most of the joint angles in four identified events reflected how the individual segments of a player's body should move. The difference in acceleration at the moment of contact between the two types of the topspin forehand was significant, but the variability of the acceleration values was small. Large variability in the angular parameters was found, and this result was considered a manifestation of different coordination patterns in the stroke movements. It is possible that even though the players used different methods of performing the movement, they obtained similar values for some parameters (e.g., acceleration), which should be taken into account by coaches. There were small differences in many parameters within individual players, which can indicate that a player performs tasks in a similar way each time. However, there was high variability in some angular parameters, indicating that the repetitions of particular strokes were not performed in an identical way. The reasons for this phenomenon include movement functionality and functional variability. [ABSTRACT FROM AUTHOR]

Effectiveness when playing in team games depends on speed-strength (jumping) abilities. The manifestations of these abilities are usually measured using tests based on vertical jumps and sprinting. This raises the question as to whether relationships exist between variables that describe the vertical jump and running time. The aim of this study was to evaluate the relationships between jumping variables, namely the height of the countermovement jump (CMJ) with arm swing and relative peak muscle power and time of the 30m-sprint (in a straight line and with direction changes) in a group of 187 young athletes who practised team sports. Measurements used a force plate and Fusion Smart Speed System. Strong significant relationships were found between the variables of the CMJ and sprint time along individual sections of the straight line and direction changes of running. However, these relationships differed between subgroups in terms of age, sporting discipline and gender. The height of the CMJ with arm swing is likely to represent a universal variable that could be used to predict the level of motor abilities among young athletes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Gait deviations may negatively affect the articular surfaces of the lower extremity joints and lead to some minor degenerative changes. The simplest method for gait evaluation is to assess the symmetry of its parameters, assuming that each undisturbed gait should be symmetrical. This study aims to quantify the degree of asymmetry of kinematic and kinetic parameters caused by the presence of different ankle orthosis settings using Dynamic Time Warping (DTW). Methods: Barefoot gait and gait with four different walker settings were investigated in eighteen healthy persons. Kinematic and kinetic parameters were measured using the Vicon system and Kistler plates. Symmetry was assessed using the DTW method. Results: It was shown that the presence of different ankle orthosis settings significantly disturbs the symmetry of all lower limb kinematic parameters and only knee and hip torques. The highest values of asymmetry were noted for the walker set at 15° of dorsiflexion (15DF). Conclusions: The DTW method allowed us to quantify the degree of asymmetry throughout the gait cycle in relation to barefoot walking. Our results suggest that each orthosis position analysed in this study fulfills its protective function, but gait 15DF can lead to the overload of knee and hip joints. [ABSTRACT FROM AUTHOR]

Low back pain (LBP) is the most frequent cause of adult disability. One of the main reasons can be a herniated disc (lumbar disc herniation—LDH), potentially disturbing spinal movement patterns. Its influence on gait and lumbopelvic biomechanics still remains unclear. Little to no evidence was found on lumbopelvic kinematics and gait in young LDH adults. The purpose of this study was to analyze the lumbopelvic biomechanics in young adult individuals with lumbar disc herniation diagnosed by MRI. Forty-three participants (18–35 years) were divided into two groups: an LDH group (n = 19) and a control group (n = 24). All participants underwent dynamic lumbopelvic and gait measures by a G-Walk wearable device in a 6-m walking test (6MWT). The Oswestry Disability Index (ODI) questionnaire was used for subjective disability assessment. The LDH group showed higher speed (p = 0.02), lower symmetry of pelvis tilt (p = 0.01), and lower pelvis rotation (p = 0.04) compared to the healthy controls. Correlation calculations showed significance between pelvis obliquity and pelvis rotation (r = 0.53) but only in healthy controls. The lumbopelvic biomechanics shows differences in pelvis tilt and symmetry index of rotation parameters between LDH and healthy controls. In conclusion, LDH affects the gait kinematics, causing three-dimensional disorders and lack of synergy. This is probably due to pain avoidance behaviors and the compensation mechanisms of the adjacent body region. [ABSTRACT FROM AUTHOR]