Michalina Błażkiewicz

The Impact of a Vestibular-Stimulating Exercise Regime on Postural Stability in People with Visual Impairment

The aim of the study was to assess the impact of a vestibular-stimulating exercise regime on postural stability in individuals with visual impairment. The study group consisted of 70 people, including 28 persons (15 female and 13 male) with visual impairment and 42 (21 female and 21 male) without visual impairment. Each individual in the group with visual impairment was medically qualified for a 3-month training program. The research methodology included medical examination, anthropometric tests, and stabilometry tests on a Biodex Balance System SD (BBS). The tests were conducted twice: once before the start of training and again after 3 months of rehabilitation. The group with visual impairment showed significantly worse postural stability results than the control group for most of the stability parameters evaluated (OSI, APSI, and MLSI). Differences were noted between the groups with and without visual impairment for dynamic tests in women and for static tests in men. After training, the two groups showed roughly similar results for the stabilometry test with eyes closed. We conclude that exercises stimulating the vestibular system with head and body movements should be recommended for individuals with visual impairments to achieve better balance retention.

A new method of determination of phases and symmetry in stand-to-sit-to-stand movement

ObjectivesDetermination of the phases in a stand-to-sit-to-stand task based on a derivative of the parameter with the lowest variance calculated based on the modified symmetry index.Material and MethodsThe study group comprised 11 healthy women and 11 healthy men from the University of Physical Education in Warsaw. The examination of the kinematic and kinetic parameters of sitting down and standing up from a chair was carried out using the Vicon Mx system and Kistler force platforms.ResultsThe modified symmetry index was employed to select the parameters used to choose those with the lowest variance. Consequently, the phases in a stand-to-sit-to-stand task were determined.ConclusionsIt was demonstrated that the task of sitting down is a reverse task with respect to standing up in terms of the symmetry of the parameters analyzed.

First signs of elderly gait for women

BACKGROUND The aims of this study have been twofold: to attempt to reduce the number of spatiotemporal parameters used for describing gait through the factor analysis and component analysis; and to explore the critical age of decline for other gait parameters for healthy women. MATERIAL AND METHODS A total of 106 women (aged ≥ 40 years old (N = 76) and ≤ 31 years old (N = 30)) were evaluated using a pressure-sensitive mat (Zebris Medical System, Tübingen, Germany) for collecting spatiotemporal gait parameters. RESULTS The factor analysis identified 2 factors - labelled Time and Rhythm - that accounted for 72% of the variation in significant free-gait parameters; the principal component analysis identified 4 of these parameters that permit full clinical evaluation of gait quality. No difference was found between the groups in terms of the values of parameters reflecting the temporal nature of gait (Rhythm), namely step time, stride time and cadence, whereas significant differences were found for total double support phase (p < 0.001). Next, seeking evidence of a critical decline in gait, we selected 3 parameters: total double support, stride time and velocity. We concluded that the women taking part in the experiment manifested significant signs of senile gait after the age of 60 years old, with the first symptoms thereof already manifesting themselves after 50 years of age. CONCLUSIONS We show that among 26 spatiotemporal parameters that may be used for characterizing gait, at least a half of them may be omitted in the assessment of gait correctness; a finding that may be useful in clinical practice. The finding that the onset of senile gait occurs in the case of women after the age of 60 years old, in turn, may be useful in evaluating the ability for performing types of physical work that mainly require ambulation. Med Pr 2017;68(4):441-448.

Effect of Drop Foot on Spatiotemporal, Kinematic, and Kinetic Parameters during Gait

Background. The complexity of the structure and function of a living body can be affected by disorders and can cause various dysfunctions. Objective. The aim of this study was to determine compensatory mechanisms in subjects with drop foot during gait. Methods. The study evaluated 10 subjects with drop foot (DF) whose results were compared to a group of 10 healthy controls (C). Spatiotemporal, kinematic, and kinetic parameters during the gait cycle were collected using Vicon system synchronized with Kistler platforms. Results. Spatiotemporal, kinematic, and kinetic parameters were significantly different between the analysed groups. In the DF group, the subjects walked almost 47% slower and performed 60% less steps per minute compared to the C group. The main problem in the DF group was insufficient ankle dorsiflexion in the 0–10% of the gait cycle. Mean values in the groups during the first 10% of the gait cycle were as follows: DF (−10.42 ± 5.7°) and C (−2.37 ± 1.47°), which affected the substantial differences in the values of muscle torque: DF (0.2 ± 0.1 Nm/kg) and C (−0.26 ± 0.06 Nm/kg). Conclusions. Comparative analysis for joint angles and torques demonstrated that the mechanism of compensation is the most noticeable in the knee joint and less in the hip joint.

Transfer of mechanical energy during the shot put

Abstract The aim of this study was to analyse transfer of mechanical energy between body segments during the glide shot put. A group of eight elite throwers from the Polish National Team was analysed in the study. Motion analysis of each throw was recorded using an optoelectronic Vicon system composed of nine infrared camcorders and Kistler force plates. The power and energy were computed for the phase of final acceleration of the glide shot put. The data were normalized with respect to time using the algorithm of the fifth order spline and their values were interpolated with respect to the percentage of total time, assuming that the time of the final weight acceleration movement was different for each putter. Statistically significant transfer was found in the study group between the following segments: Right Knee – Right Hip (p = 0.0035), Left Hip - Torso (p = 0.0201), Torso – Right Shoulder (p = 0.0122) and Right Elbow – Right Wrist (p = 0.0001). Furthermore, the results of cluster analysis showed that the kinetic chain used during the final shot acceleration movement had two different models. Differences between the groups were revealed mainly in the energy generated by the hips and trunk.

Lower limb loading during knee up in step aerobics: a pilot study

Summary Study aim: Step aerobics is a form of aerobic power distinguished from other types of aerobic exercise by its use of an elevated platform. The purpose of this study was to examine how the aerobic exercise “knee up” affects kinematic and kinetic parameters and, above all, the length of the muscle contractions. Material and methods: The study analysed ten female fitness instructors with at least six years of experience. The task consisted in the knee up move performed using a 15 cm step and music with the beat frequency of 148 BPM. Kinematic and kinetic parameters were recorded using the Vicon system synchronized with two Kistler force plates. OpenSim software was used for calculation of the length of involved muscles. Results: Ranges in angles and torques suggest that the location that is the most prone to injuries and overtraining is the knee joint, followed by the hip and ankle joints. Greater values of the vertical component of ground reaction forces were observed during stepping down, which suggests greater load to the joints. The greatest work in the move analysed in this study was performed by the sartorius muscle and the tensor fasciae latae muscle. Conclusions: Despite the benefits that have been demonstrated when step classes are structured correctly and adapted to the participants, further research is needed concerning biomechanical load, exercise prescription, and injury prevention.

EMG Comparison of Sport Manual Wheelchair Propelled by Lever Drive and Push Rims and Possible Consequences for Rehabilitation: A Case Study

The goal of this paper is to demonstrate a comparison of EMG muscle activity of a subject who conducted two 4 min long rides on a manual wheelchair using push rims and lever drive. The tests were carried out on a mechanical treadmill which allowed for maintaining constant ride conditions regarding slope and velocity of the wheelchair. The resulting muscle activity is presented in % MVC as a function of elbow joint position in deg. From this case study we conclude that it is possible that using lever drive for wheelchair propulsion activates muscles of a subject differently from push rims thus enabling a different way of muscle rehabilitation.

Types of falls and strategies for maintaining stability on an unstable surface

BACKGROUND Falls constitute an important health issue. They cause significant morbidity, mortality and have marked psychological effects on the individual, too. The aim of this study has been to determine parameters describing human movement strategies for balance and the reaction if balance is lost as a result of an unstable ground, and to attempt to describe the types of falls. MATERIAL AND METHODS The study group comprised 20 volunteers. Kinematic parameters of falling and dynamic stability were measured using the Vicon Motion System and the Biodex Balance System SD. During the test, subjects stood for 20 s on the tilting platform. The analysis was conducted based on the first recordings, when the participants were not prepared for the event and their reactions were natural. A cluster analysis tool was applied to divide the behavior of people during the test. RESULTS Based on motion range for kinematic parameters, the cluster analysis revealed 2 types of human behavior: falling (stepping) and restoring balance. Two types of falls were also observed: side and back falls. Moreover, on the basis of angular values for tilting plate, 4 zones were determined. The frequency of access to these zones by each joint revealed 3 strategies to maintain balance: ankle, knee and hip strategy. CONCLUSIONS A set of initial conditions that may be used for future numerical simulations was also determined. Furthermore, the results presented in this study are likely to support the analysis of the effects and the falling patterns. Med Pr 2018;69(3):245-252.

Are preterm-born survivors at risk of long-term respiratory disease?

Background: To evaluate the long-term impact of preterm birth on respiratory function in female patients born preterm, we undertook spirometric examinations twice, as they reached the age of puberty, then follow-up examinations of part of the same cohort in adulthood. We sought evidence that preterm birth is correlated with poorer spirometric results into adulthood. Methods: A total of 70 girls (aged 12.2 ± 1.5 years in 1997) who had been born preterm (at 34.7 ± 1.86 weeks, none having experienced bronchopulmonary dysplasia) took part in spriometric examinations in 1997 and again in 1998. Of those, after a gap of 17 years, a group of 12 were successfully recontacted and participated in the 2015 examination as adults (then aged 27.6 ± 2.6 years, born at 34.5 ± 1.92 weeks). We compared spirometric results across the adolescent and adult examinations, and compared the adult results with an adult reference group. Results: The percentage values of FEV1 (forced expiratory volume in 1 s), FVC (forced vital capacity) and MVV (maximal voluntary ventilation) showed significant improvement between the two examinations in the early adolescent period. In adulthood, FEV1%pred (percentage predicted forced expiratory volume in 1 s) showed no statistically significant difference. The mean values of both FVC and FVC%pred (percentage predicted forced vital capacity) for the preterm-born group were lower than for the reference group, but this was not statistically significant. The preterm-born group showed lower values of such parameters as forced expiratory flow at 25–75% of FVC, MEF25 (maximal expiratory flow at 25% of forced vital capacity) and FEV1/FVC as compared with the reference group, but again without statistical significance. Conclusions: (1) A somewhat below-norm level of respiratory parameters among preterm-born girls entering pubescence may attest to continued negative impact on their respiratory system. (2) A significant improvement in their spirometric results 1 year later may indicate that pubescence helps compensate for the earlier negative effect of preterm birth. (3) No significant differences were seen in lung function in preterm-born adults as compared with a reference group of adults, although the preterm-born group did exhibit lower values of all parameters studied and more frequent obstructive disorders.

Assessing the asymmetry of free gait in healthy young subjects

PURPOSE The purpose of this study was to derive reference values for a four-level scale intended to evaluate variation in free gait asymmetry measurements in healthy subjects. METHODS This evaluation is based on kinetic values for the left and right lower limbs during gait, registered with advanced measurement systems and assessed using the symmetry index (SI) developed by Robinson. RESULTS For the majority of parameters, the SI does not follow normal distribution. As such, quartile values were used to create intervals for a four-step scale of assessing symmetry of free gait in healthy subjects for each gait parameter of interest. The SI rating intervals were from 0% (very good symmetry) to 21.2% (very poor symmetry) for kinetic parameters. The poorest symmetry was observed for horizontal force F3. CONCLUSIONS The four-step scale of assessing symmetry in free gait in healthy subjects can be used in diagnosing gait disorders, devising surgical treatment strategies, and monitoring the rehabilitation process. Reference values for intervals of symmetry indicators in healthy subjects can be used as criteria for comparing individuals with/without disabilities.