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1

Asymmetry of Anticipatory Postural Adjustment During Gait Initiation

100%

Hiraoka K., Hatanaka R., Nikaido Y., Jono Y., Nomura Y., Tani K., Chujo Y.

Journal of Human Kinetics

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2014

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vol. 42

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issue 1

7-14

EN

The purpose of this study was to investigate the asymmetry of anticipatory postural adjustment (APA) during gait initiation and to determine whether the process of choosing the initial swing leg affects APA during gait initiation. The participants initiated gait with the leg indicated by a start tone or initiated gait with the leg spontaneously chosen. The dependent variables of APA were not significantly different among the condition of initiating gait with the preferred leg indicated by the start tone, the condition of initiating gait with the non-preferred leg indicated by the start tone, and the condition of initiating gait with the leg spontaneously chosen. These findings fail to support the view that the process of choosing the initial swing leg affects APA during gait initiation. The lateral displacement of the center of pressure in the period in which shifting the center of pressure to the initial swing phase before initiating gait with the left leg indicated by the external cue was significantly larger than that when initiating gait with the right leg indicated by the external cue, and significantly larger than that when initiating gait with the leg spontaneously chosen. Weight shift to the initial swing side during APA during gait initiation was found to be asymmetrical when choosing the leg in response to an external cue

2

A Pilot Study on Italian Eventing Prospective Olympic Horse Riders Physiological, Anthropometrical, Functional and Asymmetry Assessment

100%

Demarie S. D., Galvani C., Donatucci B., Gianfelici A.

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vol. 37

77-88

EN

The purpose of the study was to measure anthropometry, isometric force, balance, functional movement quality and asymmetries and peak oxygen uptake of prospective Rio 2016 Olympic Games Eventing horse riders (five males and two females: age 26-41 years, height 173.0 ± 8.9 cm, weight 66.4 ± 11.1 kg, BMI 22.0 ± 1.8, FEI ranking 33-409). Mean and maximal isometric of the hands were approximately 45 kg, and 50 kg, respectively. Total maximal isometric force of the lower limb resulted 372.6 kg for the extensor muscles, and approximately 58 kg for the adductor muscles. Mean composite functional movement score was 14.1, mean Bunkie score 3.4. Y-balance score 93.1 ± for the left side and 90.9 for the right one. V̇O2peak values ranged between 2.4 and 4.2 l·min-1 and 46.8 and 59.7 ml·kg-1·min-1. The oldest and more experienced athletes had a greater postural control on the anterior direction. The athletes with a superior FEI ranking had a greater postural control. Subjects had high maximal isometric strength of the hands and lower limbs, good physical functions parameters, balance and maximal aerobic power and few muscular strength and balance asymmetries.

3

Analysis of Body Posture Between Young Football Players and their Untrained Peers

100%

Grabara M.

Human Movement

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2012

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vol. 13

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issue 2

120-126

EN

Purpose. The aim of this study was to analyze the body posture of young football players and their untrained peers. Methods. A group of 73 football players and 78 untrained boys, all aged between 11 and 14 years, were studied by measuring body posture indices with computer posturography (the MORIE technique). Spinal angles and curvatures in the sagittal plane and body posture asymmetry in the frontal and transversal plane were measured. Body height and mass and BMI were also determined. Results. Compared to the untrained boys, the group of football players had lower BMI. The position of pelvis in the frontal plane was more symmetrical (p < 0.001) in football players, but the alignment of the remaining measured parameters was similar between the two groups except for the horizontal symmetry of the waist triangles (a higher incidence of symmetry in some ages groups of football players) and the horizontal symmetry of the shoulder blades (a higher incidence of asymmetry in some ages groups of football players). A postural symmetry index that was created for this study did not find any differentiation among the studied groups. The spinal alignment of the football players featured a more flattened lumbar lordosis. Conclusion. Previously conducted studies on the body posture of young athletes are still not ample and complete, while the results do not clearly indicate the development of posture when subjected to sports training.

4

On the rotational dynamics of the rattleback

88%

Franti L.

Open Physics

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2013

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vol. 11

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issue 2

162-172

EN

The rattleback is a very popular science toy shown to students all over the world to demonstrate the nontriviality of rotational motion. When spun on a horizontal table, this boat-shaped object behaves in a peculiar way. Although the object appears symmetric, the dynamics of its motion seem very asymmetric. When spun in the preferred direction, it spins smoothly, whereas in the other direction it starts to oscillate wildly. The oscillation soon dies out and the rattleback starts to spin in the preferred way. We will construct and go through an analytical model capable of explaining this behaviour in a simple and intelligible way. Although we aim at a semi-pedagogical treatise, we will study the details only when they are necessary to understand the calculation. After presenting the calculations we will discuss the physical validity of our assumptions and take a look at more sophisticated models requiring numerical analysis. We will then improve our model by assuming a simple friction force.

5

Hemifacial asymmetries in age perception: the left cheek looks older for females, but not males

88%

Lindell A. K., Cianchetta R. O., Azim S. M., Freeman C. G., de Oliveira N. C., Saban S., Messina J. L., Wilson K. E., Egan A., Caspar M. D., Grey E. J., McDonald B. A., Croxford K. N., Bui T. T., Aiello A. A., Heywood-Smith V. M., Kidd A. J., Stanley S. C., Wakeling A., Hoggan S. A. L., Morriss A. S., Trinh T. P. M., Thai-Nguyen H., Fonte M., Agolli F.

Acta Neuropsychologica

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2019

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vol. 17(4)

417-426

EN

The left hemiface expresses emotion more intensely than the right. Because emotional expressions contract the facial muscles and wrinkle the skin, theoretically the left hemiface’s greater expressivity should prompt more pronounced expression lines and wrinkles on the left than right side of the face. As wrinkles are the most salient age cue, we investigated whether the left hemiface consequently appears older than the right. Two hundred and sixty participants (F=148; M=112) viewed booklets containing pairs of left-left and right-right chimeric faces of eight models (M=F). For each trial participants were asked to make a two alternative forced choice response indicating which image looked older. Results confirmed a left cheek bias, with participants more likely to select left-left than right-right chimeras. Whilst participant gender did not influence perceptions, model gender predicted cheek selections: responses to female models drive the overall left cheek bias. The left cheek (56.8%) appeared older than the right cheek (43.2%) for female models, whereas there was little difference in perceived age between male models' left (50.8%) and right (49.2%) cheeks. Given that youth influences perceptions of female beauty, these findings complement previous research and offer a potential explanation for why the left side of females’ faces are judged less attractive: the right cheek appears younger.

6

Kratery Morasko w świetle wiedzy na temat ukośnych impaktów

75%

Walesiak T.

Acta Societatis Metheoriticae Polonorum

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2017

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vol. 8

149-168

EN

It is considered that The Morasko meteorite shower happened about 5400 years BP with a trajectory from NE to SW (Bronikowska et al. 2015). Recent studies not only prove that this fall could be observed in Februrary 14, 1271, but also that location of most findings in the area to the east side of the craters, should not be taken as the main indicator of impact direction. The proper answer can be given base on knowledge related to oblique impacts, supported by understanding of complicated fragmentation process. The largest crater in Morasko Meteorite Restricted Area has main ejecta plume located in SE, side walls in SW and NE, and free of ejecta Zone of Avoidance (ZoA) in NW. This clearly shows that impact trajectory was approximatelly from NW to SE. There were also discovered other structures, 2 km North from Restricted Area, having common features. Their ejecta plumes as well as few raised ducts (possible traces of underground penetration) are directed to SE, pointing the largest structure – Umultowskie Lake, located approx. 2 km ESE from known main Morasko crater. Shapes of cavities, their walls and ejecta asymmetry allow estimating trajectories and defining new Morasko strewnfield, which matches not only location of impact strucures and discovered meteorite fragments, but also explains smaller (3–4 kg) findings in the neighborhood of Oborniki Wielkopolskie.

7

Posture, Flexibility and Grip Strength in Horse Riders

75%

Hobbs S. J., Baxter J., Broom L., Rossell L.-A., Sinclair J., Clayton H. M.

Journal of Human Kinetics

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2014

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vol. 42

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issue 1

113-125

EN

Since the ability to train the horse to be ambidextrous is considered highly desirable, rider asymmetry is recognized as a negative trait. Acquired postural and functional asymmetry can originate from numerous anatomical regions, so it is difficult to suggest if any is developed due to riding. The aim of this study was therefore to assess symmetry of posture, strength and flexibility in a large population of riders and to determine whether typical traits exist due to riding. 127 right handed riders from the UK and USA were categorized according to years riding (in 20 year increments) and their competition level (using affiliated test levels). Leg length, grip strength and spinal posture were measured and recorded by a physiotherapist. Standing and sitting posture and trunk flexibility were measured with 3-D motion capture technology. Right-left differences were explored in relation to years riding and rider competitive experience. Significant anatomical asymmetry was found for the difference in standing acromion process height for a competition level (-0.07±1.50 cm Intro/Prelim; 0.02±1.31 cm Novice; 0.43±1.27 cm Elementary+; p=0.048) and for sitting iliac crest height for years riding (-0.23±1.36 cm Intro/Prelim; 0.01±1.50 cm Novice; 0.86±0.41 cm Elementary+; p=0.021). For functional asymmetry, a significant interaction was found for lateral bending ROM for years riding x competition level (p=0.047). The demands on dressage riders competing at higher levels may predispose these riders to a higher risk of developing asymmetry and potentially chronic back pain rather than improving their symmetry

8

Further developments in PAC method of adjustment of geodetic networks

75%

Dumalski A., Dumalski A.

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2006

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vol. 55

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issue 2

9

H:Q Ratios and Bilateral Leg Strength in College Field and Court Sports Players

75%

Cheung R., Smith A., Wong D.

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EN

One of the key components in sports injury prevention is the identification of imbalances in leg muscle strength. However, different leg muscle characteristics may occur in large playing area (field) sports and small playing area (court) sports, which should be considered in regular injury prevention assessment. This study examined the isokinetic hamstrings-to-quadriceps (H:Q) ratio and bilateral leg strength balance in 40 male college (age: 23.4 ± 2.5 yrs) team sport players (field sport = 23, soccer players; court sport = 17, volleyball and basketball players). Five repetitions of maximal knee concentric flexion and concentric extension were performed on an isokinetic dynamometer at two speeds (slow: 60 °·s-1 and fast: 300°·s-1) with 3 minutes rest between tests. Both legs were measured in counterbalanced order with the dominant leg being determined as the leg used to kick a ball. The highest concentric peak torque values (Nm) of the hamstrings and quadriceps of each leg were analyzed after body mass normalization (Nm·kg-1). Court sport players showed significantly weaker dominant leg hamstrings muscles at both contraction speeds (P < 0.05). The H:Q ratio was significantly larger in field players in their dominant leg at 60°·s-1 (P < 0.001), and their non-dominant leg at 300°·s-1 (P < 0.001) respectively. Sport-specific leg muscle strength was evident in college players from field and court sports. These results suggest the need for different muscle strength training and rehabilitation protocols for college players according to the musculature requirements in their respective sports.

10

Analiza cech impaktu ukośnego na przykładzie struktur Porządzie, Jaszczułty i Ochudno

75%

Walesiak T.

Acta Societatis Metheoriticae Polonorum

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2016

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vol. 7

151-176

EN

It’s considered that one half of all projectiles are striking surface of planets at the angle lower than 45°. Our knowledge of oblique impact events is based on computer modelling, laboratory experiments and observation of craters on the Moon, Mars, Venus and other celestial bodies. Recent discovery in northeast Poland, reveals at least four structures with features reserved for low-angle impacts. In this article we show and explain them using high-quality laser air scanning data (LiDAR) in comparison to results of experiments and similar real known objects on other planets. Also we try to verify by analyzing historical sources if multiple impact event could occur in our area and, if it was noticed and reported in the papers.

11

THE APPLICABILITY OF USING PARAMETERS OF THE AUTOCORRELATION FUNCTION IN THE ASSESSMENT OF HUMAN BALANCE DURING QUIET BIPENDAL STANCE

75%

Stodółka J., Korzewa L., Stodółka W., Gambal J.

Central European Journal of Sport Sciences and Medicine

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2017

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vol. 17

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issue 1

79-87

EN

The purpose of the study was to analyze the parameters of the autocorrelation function when assessing time series ground reaction force (GRF) signals during quiet standing. GRF in the three directions were recorded on two Kistler force plates during three 15-s trials in a sample of 82 (31 females and 51 males) participants. Autocorrelation was performed on the GRF data and four parameters characterizing the function were computed. Comparisons of the right- and left-foot parameter means showed significant differences in mediolateral GRF for the time of the function's decay to 0, magnitude of the derivative output, and mean decay velocity to the extremum. Significant correlations were observed among all parameters – weak correlations between the time of the function's decay to 0 and the time to the first extremum and strong correlations between the derivative output and mean decay velocity to the extremum. The analyzed autocorrelation function parameters can serve as a precise measure of the motor control process during quiet standing. The strong correlations observed between the four parameters indicate that they evaluate similar properties of the central nervous system as a regulator of balance maintenance.

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Asymmetry of Anticipatory Postural Adjustment During Gait Initiation

A Pilot Study on Italian Eventing Prospective Olympic Horse Riders Physiological, Anthropometrical, Functional and Asymmetry Assessment

Analysis of Body Posture Between Young Football Players and their Untrained Peers

On the rotational dynamics of the rattleback

Hemifacial asymmetries in age perception: the left cheek looks older for females, but not males

Kratery Morasko w świetle wiedzy na temat ukośnych impaktów

Posture, Flexibility and Grip Strength in Horse Riders

Further developments in PAC method of adjustment of geodetic networks

H:Q Ratios and Bilateral Leg Strength in College Field and Court Sports Players

Analiza cech impaktu ukośnego na przykładzie struktur Porządzie, Jaszczułty i Ochudno

THE APPLICABILITY OF USING PARAMETERS OF THE AUTOCORRELATION FUNCTION IN THE ASSESSMENT OF HUMAN BALANCE DURING QUIET BIPENDAL STANCE