scholarly journals Comportamento tático coletivo em Pequenos Jogos no Futebol: influência de jogadores adicionais

2016 ◽  
Vol 18 (1) ◽  
pp. 62 ◽  
Author(s):  
Gibson Moreira Praça ◽  
Hugo Folgado ◽  
André Gustavo Pereira de Andrade ◽  
Pablo Juan Greco
Keyword(s):  
The Other ◽  
Soccer Players ◽  
Width Ratio ◽  
Collective Variables ◽  
Other Hand ◽  
Centroid Distance ◽  
Friedman's Test ◽  
Polar Coordinate ◽  
Length Width ◽  
Positional Data

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n1p62 The aim of this study was to compare the collective tactical behavior between numerically balanced and unbalanced small-sided soccer games. Eighteen male soccer players (mean age 16.4 years) participated in the study. Polar coordinate analysis was performed using positional data obtained with a 15-Hz GPS device. Collective variables including length, width, centroid distance (average point between teammates), and length per width ratio (LPWratio) were collected. Data were analyzed using Friedman’s test. The results showed greater length and width values in 4vs.3 games, while a higher LPWratiowas observed in 3vs.3+2 games compared to the other configurations. In games with an additional player (4vs.3), ball circulation and the increase in effective game space were alternatives to overcome the more concentrated defensive systems near the goal. On the other hand, 3vs.3+2 games allowed more actions in the length axis and a fast reach of the opponent’s goal.

scholarly journals Effects of match period and playing position on the individual and collective dynamics in professional soccer: a case study

2020 ◽  
Vol 22 ◽  
Author(s):  
Gibson Moreira Praça ◽  
André Gustavo Pereira de Andrade ◽  
Sarah da Glória Teles Bredt ◽  
Pedro Emilio Drumond Moreira ◽  
Gustavo De Conti Teixeira Costa ◽  
...  
Keyword(s):  
T Test ◽  
Soccer Players ◽  
Width Ratio ◽  
Collective Variables ◽  
Professional Soccer ◽  
Spatial Exploration ◽  
The Individual ◽  
Positional Data ◽  
Paired T Test

Abstract This study aimed to compare the width, the length, the length per width ratio, and the stretch index between the first and the second halves in official soccer matches, and to compare the spatial exploration index between players from different positions. Seventeen professional soccer players from a Brazilian club participated in the study and were monitored during six official matches by a GPS device. Collective positional data were compared between the two halves using a paired t-test, while the spatial exploration index was compared between the playing positions and within the halves by a mixed two-way ANOVA. The results revealed no differences between the two halves for the collective variables. The highest values of spatial exploration index were reported for central midfielders and wing forwards. We conclude that the tactical behavior of professional soccer players is position-dependent, and midfielders are the most exploratory players on the pitch.

scholarly journals Eccentric-Overload Production during the Flywheel Squat Exercise in Young Soccer Players: Implications for Injury Prevention

2020 ◽  
Vol 17 (10) ◽  
pp. 3671
Author(s):  
Javier Raya-González ◽  
Daniel Castillo ◽  
Marta Domínguez-Díez ◽  
José Luis Hernández-Davó
Keyword(s):  
Injury Prevention ◽  
Peak Power ◽  
Power Production ◽  
The Other ◽  
Soccer Players ◽  
Other Hand ◽  
Squat Exercise ◽  
Resistance Exercises ◽  
Eccentric Overload

This study aimed to evaluate the differences in power production between movement phases (i.e., concentric and eccentric) during the execution of resistance exercises with a flywheel device, differentiating between execution regimes (i.e., bilateral, unilateral dominant leg and unilateral non-dominant leg). Twenty young elite soccer players (U−17) performed two sets of six repetitions of the bilateral half-squat (inertia 0.025 kg·m−2) and the lateral-squat exercise (inertia 0.010 kg·m−2) on a flywheel device. During the testing sessions, mean and peak power in concentric (MPcon) and eccentric (MPecc) phases were recorded. The non-dominant leg showed higher values in all power variables measured, although substantial differences were only found in MPecc (ES = 0.40, likely) and PPcon (ES = 0.36, possibly). On the other hand, for both exercises, MPcon was higher than MPecc (ES = −0.57 to −0.31, possibly/likely greater), while only PPecc was higher than PPcon in the dominant lateral-squat (ES = 0.44, likely). These findings suggest that young soccer players have difficulty in reaching eccentric-overload during flywheel exercises, achieving it only with the dominant leg. Therefore, coaches should propose precise preventive programs based on flywheel devices, attending to the specific characteristics of each limb, as well as managing other variables to elicit eccentric-overload.

scholarly journals Manipulating the Pitch Size Constrains the Players’ Positioning during Unbalanced Soccer Small-Sided Games Played by Different Age Groups

Kinesiology ◽  
2021 ◽  
Vol 53 (2) ◽  
pp. 206-214
Author(s):  
Gibson Moreira Praca ◽  
André Gustavo Pereira de Andrade ◽  
Cristóvão de Oliveira Abreu ◽  
Pedro Emilio Drumond Moreira ◽  
Filipe Manuel Clemente ◽  
...  
Keyword(s):  
Age Groups ◽  
Width Ratio ◽  
Complex Task ◽  
Age Group ◽  
Task Context ◽  
Length Width ◽  
Spatial Exploration ◽  
Pitch Length ◽  
The Impact ◽  
Positional Data

We aim to investigate the impact of variable soccer pitch sizes on the position of players during unbalanced small-sided games (SSGs) and compare the responses of players from two different age groups. Forty-eight young players (n = 24 under-13 and n = 24 under-14) took part in the study and played 3 vs. 3 + 1 SSGs on two different pitch sizes (smaller: 36 x 27 m / 139m2 per player; and larger: 40 x 29 m / 166 m2 per player). Players’ positions on the pitch (length, width, length-to-width ratio, stretching index, and spatial exploration index) were assessed by the positional data provided by global position system devices and were compared within age groups and between game formats using a two-way analysis of variance. Results showed higher values of spatial exploration index in the larger SSGs than in the smaller format (p<.001). Moreover, a higher length (p<0.001) and length-to-width ratio (p<.001) was observed in the younger group. Finally, the larger format presented higher values of SEI and stretching index, independent of the age group (p<.001). In the smaller format, U-14 players presented a higher stretching index, while in the larger format U-13 players presented higher values in the same variable. We conclude that enlarging the pitch size constrains players’ behaviour during SSGs, and older players are more able to deal with this more complex task context than younger ones.

Clumpy artifacts can be differentiated from tophi with DECT: comparison between gout-free and gouty patients

2021 ◽  
Author(s):  
Dong Han Shin ◽  
You Seon Song ◽  
Yunjung Choi ◽  
Wan-Hee Yoo ◽  
Florian Kummel ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Cross Section ◽  
The Other ◽  
Width Ratio ◽  
Foot And Ankle ◽  
Anatomic Location ◽  
Other Hand ◽  
Almost All ◽  
Oval Shape

Objectives: To accurately differentiate clumpy artifacts and tophi with foot and ankle DECT. Methods and materials: In session 1, 108 clumpy artifacts from 35 patients and 130 tophi images from 25 patients were analyzed. Reviewers classified green pixelation according to anatomic location, shape (linear, stippled, angular, oval), and height and width ratio. In session 2, green pixelation confined to the tendon was evaluated (shape, height and width ratio, occupied area in the tendon, accompanied peritendinous green pixelation). Results: In session 1, while tophi were noted at various locations, almost all clumpy artifacts were located at the tendon (99%, p < 0.0001). Most clumpy artifacts were linear, stippled, and wide, while most tophi were angular and oval (p < 0.05). In session 2, the shape of green pixelation from clumpy artefact and tophi was significantly different (p < 0.0001) and most clumpy artifacts occupied less than 50% of the tendon (p = 0.02), and most tophi were accompanied by peritendinous green pixelation (p < 0.0001). Univariant logistic regression showed that tophi were significantly correlated with peritendinous deposits, angular and oval shape, and more than 50% of the tendon (p < 0.05). Conclusion: Clumpy artifacts can be differentiated from tophi in DECT. Clumpy artifacts typically are located in the tendon with a linear or stippled shape, wide, and less than 50% of a tendon’s cross-section. Tophi, on the other hand, typically are oval, larger than 50% of the tendon’s cross-section, and associated with adjacent peritendinous green pixelation. Advances in knowledge: Clumpy artifacts can be differentiated from tophi in image findings by their location and shape.

scholarly journals 5-Chloro-3-ethylsulfinyl-7-methyl-2-(4-methylphenyl)-1-benzofuran

2014 ◽  
Vol 70 (4) ◽  
pp. o458-o458
Author(s):  
Hong Dae Choi ◽  
Pil Ja Seo ◽  
Uk Lee
Keyword(s):  
Dihedral Angle ◽  
Title Compound ◽  
Ring System ◽  
The Other ◽  
Axis Direction ◽  
Π Interactions ◽  
Compound C ◽  
Other Hand ◽  
Centroid Distance ◽  
The Mean

In the title compound, C18H17ClO2S, the dihedral angle between the mean planes of the benzofuran ring system and the methylphenyl ring is 14.50 (4)°. The centroid–centroid distances between the benzene and the methylphenyl rings are 3.827 (2) and 3.741 (2) Å, while the centroid–centroid distance between the furan and methylphenyl rings is 3.843 (2) Å. These distances indicate π–π interactions; on the other hand, the interplanar angles between the benzene and methylphenyl rings, and between the furan and methylphenyl rings are 13.89 (4) and 15.53 (4)°, respectively. In the crystal, the molecules stack along thea-axis direction.

scholarly journals Shorter Small-Sided Game Sets May Increase the Intensity of Internal and External Load Measures: A Study in Amateur Soccer Players

Sports ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 107
Author(s):  
Filipe Manuel Clemente ◽  
Pantelis Theodoros Nikolaidis ◽  
Thomas Rosemann ◽  
Beat Knechtle
Keyword(s):  
Heart Rate ◽  
External Load ◽  
Perceived Exertion ◽  
The Other ◽  
Soccer Players ◽  
Internal Load ◽  
Other Hand

The purpose of this study was to compare internal and external load measures during two regimens (6 x 3’ and 3 x 6’) of a 5 vs. 5 format of play. Moreover, within-regimen changes (between sets) were also tested. Ten amateur soccer players (age: 19.8 ± 1.6 years; experience: 8.3 ± 2.1 years; height: 177.4 ± 3.8 cm; weight: 71.7 ± 4.2 kg) participated in the experiment. Internal load was measured using the CR-10 scale as the rated of perceived exertion (RPE) scale and a heart rate (HR) monitor. The measurements of total (TD), running (RD) and sprinting (SD) distances were also collected using a 10-Hz validated and reliable GPS. Comparisons between regimens revealed that the 3 x 6’ regimen was significantly more intense in terms of RPE than the 6 x 3’ regimen (p = 0.028; d = 0.351), although no significant differences were found in HR. Significantly greater averages of TD (p = 0.000; d = 0.871) and RD (p = 0.004; d = 0.491) were found in the 6 x 3’ regimen. In both regimens, the RPE was significantly lower during the first set than in the remaining sets. On the other hand, the TD was significantly shorter in the last sets than in the earlier. In summary, the present study suggests that shorter sets may be beneficial for maintaining higher internal and external load intensities during 5 vs. 5 formats, and that a drop-in performance may occur throughout the sets in both regimens.

scholarly journals VARIASI MORFOMETRIK DAN ALLOZYME CALON INDUK RAJUNGAN, Portunus pelagicus DARI BEBERAPA PERAIRAN DI INDONESIA

2006 ◽  
Vol 1 (2) ◽  
pp. 235
Author(s):  
Gusti Ngurah Permana ◽  
Sari Budi Moria ◽  
Haryanti Haryanti ◽  
Bambang Susanto
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Component Analysis ◽  
Allozyme Variation ◽  
The Other ◽  
Width Ratio ◽  
Portunus Pelagicus ◽  
Central Java ◽  
South Sulawesi ◽  
Other Hand

Sampel diambil dari empat populasi rajungan yang berbeda yaitu Sulawesi Selatan, Jawa Timur, Jawa Tengah, dan Bali. Penelitian ini dilakukan untuk mengetahui variasi morfometrik dan allozyme dari calon induk rajungan. Hasil yang diperoleh yaitu variasi genetik rata-rata keempat populasi sangat rendah (0,0025). Rajungan dari Jawa Tengah dan Bali mempunyai nilai heterosigositas tertinggi yaitu 0,004 sedangkan populasi Sulawesi Selatan dan Jawa Timur (0,001). Jarak genetik populasi Jawa Timur dan Bali (0,0013), kemudian Jawa Tengah (0,0016), dan Sulawesi Selatan (0,002). Uji analisis komponen utama (Principal component analysis, PCA), menunjukkan bahwa secara morfometrik rajungan jantan dan betina yang berasal dari populasi Cilacap-Jawa Tengah dan P. Saugi-Sulawesi Selatan dapat membentuk satu sub populasi yang sama, sebaliknya populasi asal Negara-Bali membentuk sub populasi tersendiri. Korelasi yang erat antara nisbah panjang dan lebar karapas terhadap bobot tubuh ditemukan pada populasi P. Saugi-Sulawesi Selatan dan Cilacap-Jawa Tengah sebaliknya pada populasi Negara-Bali mempunyai korelasi yang rendah.Samples were collected from South Sulawesi, Central Java, East Java, and Bali. Genetic variation from allozyme was consistently low in all populations (0.0025) This research aimed to know morphometric and allozyme variation of Swimming Blue Crab, Portunus pelagicus from Indonesian waters. Population from Central Java and Bali had the highest heterozigosity value (0.004) compare to those from South Sulawesi and East Java (0.001). Sample cluster according to the pair’s genetic distance showe that East Java and Bali population has the smallest value (0.0013). By contrast, the largest value was observed in Central Java (0.0016) and South Sulawesi population (0.002). Principal Component Analysis showed that morphometrically male and female swimming blue crabs from Saugi and Cilacap population can build one identical subpopulation On the other hand population originated from Negara made a separate subpopulation There high correlation between carapace length and width ratio on population of P. Saugi-South Sulawesi and Cilacap-Central Java, on the other hand, Negara-Bali population had a low correlation.

Description of two new Cymbella (Bacillariophyta) species from Sakarbaşı spring, Turkey

Phytotaxa ◽  
2021 ◽  
Vol 484 (2) ◽  
pp. 195-206
Author(s):  
CÜNEYT NADIR SOLAK ◽  
NESLIHAN BALKIS-OZDELICE ◽  
ELIF YILMAZ ◽  
TURGAY DURMUS ◽  
SAÚL BLANCO
Keyword(s):  
New Species ◽  
The Other ◽  
Width Ratio ◽  
Sakarya River ◽  
Length Width

The descriptions of the new species Cymbella balkii sp. nov. and C. yerlii sp. nov. were given in this study. The species were found in a karstic limnocrene spring which is one of the most important sources of Sakarya River. Cymbella balkii sp. nov. is very similar to C. pervarians, C. simonsenii, C. percymbiformis, C. perparva, C. alpestris and C. vulgata. Among them, C. pervarians is the most similar taxon however, the former has higher stigmata number and larger valve than the latter. Cymbella yerlii sp. nov. is very similar to C. parva, C. perparva and C. parviformis are similar taxa. Among them, C. parva is the most similar taxon in all related ones with similar outline. However, length/width ratio is higher in C. yerlii than the other taxa.

Comparative Geographical Variation in Seedling Morphology of Three Closely Related Red Mahoganies, Eucalyptus Urophylla, E. pellita and E. scias

1993 ◽  
Vol 41 (1) ◽  
pp. 23 ◽  
Author(s):  
K Pinyopusarerk ◽  
BV Gunn ◽  
ER Williams ◽  
LD Pryor
Keyword(s):  
New Guinea ◽  
Leaf Length ◽  
The Other ◽  
Canonical Variate ◽  
Width Ratio ◽  
Eucalyptus Urophylla ◽  
Seedling Morphology ◽  
The North ◽  
Northern Cape ◽  
Length Width

Twenty two populations of Eucalyptus urophylla, 13 of E. pellita and two of E. scias were selected throughout the species' natural distributions in Indonesia, Papua New Guinea and Australia, and the morphology of seedlings compared under greenhouse conditions. Leaf length, width, length/width ratio, base angle, stem shape and, to a lesser extent, intranode length provided good discrimination between species and provenances. Canonical variate analysis revealed four groups, two of which contain E. urophylla, one E. pellita and one E. scias. Wetar Island provenances formed one of the two E. urophylla groups, distinguished from the other group consisting of Alor, Adonara, Flores, Pantar and Timor provenances on the basis of narrower leaves, greater length/width ratios, more acute leaf base angles and square stems. Seedling leaves of E. pellita were generally longer and broader than the other species, with a tendency for a separation between the northern occurrences (New Guinea and northern Cape York Peninsula, Queensland) and southern occurrences (Helenvale to Rockhampton, Queensland); those from the north had smaller leaves and more distinctly square stems. E. scias is clearly distinguished by its narrower leaves and longer intranode length.

Designing facilitated task constraints for different age groups in soccer: The impact of floaters’ rules

2021 ◽  
pp. 174795412110174
Author(s):  
Gibson Moreira Praça ◽  
Pedro Emílio Drumond Moreira ◽  
Marcelo Rochael ◽  
Gustavo Barbosa ◽  
Bruno Travassos
Keyword(s):  
Age Groups ◽  
Group Differences ◽  
Width Ratio ◽  
Task Constraints ◽  
Youth Soccer ◽  
Length Width ◽  
Spatial Exploration ◽  
Gps Devices ◽  
The Impact ◽  
Positional Data

This study compared the influence of changing floaters’ rules on player positioning in small-sided games (SSG) played by different age groups. A total of 48 youth soccer players (24 U-13 and 24 U-14) took part in the study, playing three different SSGs: regular 3vs3, 1-floater condition (one floater playing for both teams), and 2-floater condition (one floater per team, with alternate participation). Positional data were collected by 5 Hz GPS devices, generating individual (spatial exploration index) and collective (team’s length, width, length per width ratio, and stretching index) positional variables. The results revealed that the 2-floater format significantly reduced the length (p = 0.001), and both formats with floaters increased the width (p < 0.001). Also, the 1-floater format presented the lowest stretching index (p < 0.001). Concerning age-group differences, older players presented higher values of length (p < 0.001), length per width ratio (p < 0.001), and spatial exploration index (p < 0.001) than their younger counterparts. The 2-floater SSG format is a more facilitated and simplified version of numerically unbalanced SSGs, which might be considered by coaches when designing tasks adjusted to the level of the athletes.

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