The influence of the field orientation on physical demands in soccer small-sided games

Author(s):  
Marcelo S. Luchesi ◽  
Bruno P. Couto ◽  
Tim J. Gabbett ◽  
Gibson M. Praça ◽  
Mariana P. Oliveira ◽  
...  

The aim of this study was to compare the physical demands of SSG with either greater length (SSGlength) or width (SSGwidth) with official soccer matches. Sixteen Brazilian U-20 national-level soccer players participated in two sessions with SSGlength (4v4, 40 m length and 26 m width) and two sessions with SSGwidth (4v4, 26 m length and 40 m width). External and internal load variables were monitored and compared to official games (12.8 ± 8.9 games per player). Data were standardized to the time and compared between the experimental conditions by a one-way analysis of variance (ANOVA) with repeated measures (level of significance set at p < 0.05). The effect size was calculated by the partial ETA squared (ɳ p2). Results showed that the total distance covered during SSGlength was significantly higher compared to official matches (8.1%; p = 0.001) and SSGwidth (5.2%; p = 0.049). Highest values were registered in the matches when compared to SSGlength and SSGwidth for high-speed distance, sprint distance, maximal speed and number of sprints. The number of accelerations was significantly lower during official matches than SSGwidth (36.5%; p = 0.002) and SSGlength (45.0%; p < 0.001). The number of high-speed actions was higher in official games when compared to SSGwidth (47.1%; p < 0.001). No differences were found between matches and SSGlength ( p = 0.059). We concluded that the physical demands of the 4v4 SSGs adopted in this study were different from the physical demands of official match play. The use of a field with a greater width rather than length does not appear to make the physical demands of the SSG more similar to the official games.

Author(s):  
Roberto Modena ◽  
Andrea Togni ◽  
Maurizio Fanchini ◽  
Barbara Pellegrini ◽  
Federico Schena

Abstract Purpose To analyse the influence of goalkeepers during 4-a-side small-sided games, played in pitches of two different sizes (small: 30 × 20 m, large: 40 × 30 m). Methods Total distance covered (TD), distance covered at low- (LSD), moderate- (MSD), high- (HSD) and very high-speed (VHSD), average and maximal speed, Edwards’ training load (Edw-TL), time spent above 90% of maximal heart rate (T90%) and rate of perceived exertion (RPE) were monitored, in 18 amateur soccer players. Results Higher TD (mean difference: + 181 m, Hedge’s g: 0.93 and + 400 m, 3.37), MSD (+ 85 m, 0.79 and + 146 m, 1.64), HSD (+ 101 m, 1.41 and + 179 m, 3.26), VHSD (+ 30 m, 1.89 and + 35 m, 1.26), average speed (+ 0.65 km h−1, 0.88 and + 1.47 km h−1, 3.31) and maximal speed (+ 3.60 km h−1, 1.40 and + 3.58 km h−1, 1.40) were found in large than small pitch, without and with goalkeepers, respectively. Goalkeeper’s presence increased Edw-TL (+ 8.4 AU, 0.70) and reduced TD (− 141 m, 0.75), HSD (− 54 m, 0.75) and average speed (− 0.54 km h−1, 0.76) in small pitch and maximal speed (1.59 km h−1, 0.60 and 1.61 km h−1, 0.66) in both small and large pitches, respectively. RPE was higher (+ 20, 1.52) in the large than small pitch when the goalkeepers were present. Conclusion Implementing small-sided games, coaches should be aware that lower external load with similar internal load could be provided using small pitch with goalkeeper rather than either small goals or larger pitch. Furthermore, large small-sided games without goalkeeper may be the best choice for eliciting high training load.


2021 ◽  
Vol 11 (4) ◽  
pp. 1756
Author(s):  
Shane Malone ◽  
Kieran Collins ◽  
Allistair McRobert ◽  
Dominic Doran

The current investigation quantified the training and match-play load of elite Gaelic football players across a two-season period using global positioning system technology (GPS), rating of perceived exertion (RPE) and sessional rating of perceived exertion (sRPE). Total weekly workload variables were collected across GPS, RPE, and sRPE across thirty-six elite Gaelic footballers (mean ± SD, age: 26 ± 5 years; height: 177 ± 8 cm; mass: 81 ± 7 kg) from one elite squad during a two-season observational period. External training load variables included: Total distance (m), High speed running (m; ≥ 17.1 km·h−1), Sprint distance (m; 22 km·h−1), Accelerations (n), Average metabolic power (W·kg−1), High-power distance (m; ≥ 25 W·kg−1). Internal load variables included: sRPE and RPE. Repeated measures ANOVA were used to understand the differences in loading patterns across phases, position, and week types when significant main effects were observed a Tukey’s post hoc test was applied and standardized effect sizes were calculated to understand the practical meaning of these differences. When total weekly loading across phases was considered total load was significantly greater in club 1 and provincial 1 with these phases showing the highest loading for players when compared to all other phases (p ≤ 0.001; ES: 2.95–7.22; very large). Furthermore, in-season 1 was greater for total loading when compared to in-season 2 and both championship phases (p ≤ 0.05; ES: 0.47–0.54; small). Total distance in training was greater during preseason 1 when compared to all other phases of the season (p ≤ 0.001; ES: 2.95–7.22; very large). During the in-season period, training based total distance was higher during provincial 1 when compared to other phases with similar trends across all measures (p ≤ 0.005). Finally, a positional profile for load measures was observed, with weekly context (match or non-match) having an impact on the internal and external loading players experienced across phases. The current data provide useful information for practitioners on the training periodization currently present within the elite Gaelic football training process. Specifically, the data provide positional profiles of loading across weekly and segmented phased of an elite Gaelic football season. These data can increase understanding as to the periods of increased and decreased loading across different phases of an elite Gaelic football season, while providing a framework for future analysis concerning Gaelic football periodization.


Kinesiology ◽  
2016 ◽  
Vol 48 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Jonatas Ferreira da Silva Santos ◽  
Tomás Herrera-Valenzuela ◽  
Gustavo Ribeiro da Mota ◽  
Emerson Franchini

The aim of this study was to assess the effects of different postactivation potentiation conditioning activities’ volumes and intensities on countermovement jump and multiple sets of high speed kicks. Nine taekwondo athletes (M±SD; age: 20.3±5.2 years; height: 177±7.2 cm; body mass: 71.8±15.3 kg; maximum dynamic half-squat 1RM: 132.8±32.5 kg and practice time: 9.6±7.2 years) participated. One control and four experimental conditions were randomly applied. Each condition was composed of warm-up, conditioning activity (half-squat: 1x3 at 50 or 90% 1RM or 3x3 at 50 or 90% 1RM), followed by a 10-minute rest interval, a countermovement jump and five sets of Frequency Speed of Kick Test. The conditions were compared using an analysis of variance with repeated measures, followed by Bonferroni post-hoc test. The alpha level was set at 5%. The significant difference was found in the number of kicks among sets (F3,21;128,36=25.34; p&lt;.001; η2=.388 [small]). The rating of perceived exertion before control condition was higher than in all experimental protocols (F4,32=6.64; p=.001; η2=.454 [small]). There were no effects of volume and intensity on the variables investigated (maximum countermovement jump, mean countermovement jump, kick decrement, impact and rating of perceived exertion). Our results indicate that taekwondo athletes does not improve performance after conditioning activities of different volumes and intensities.


2020 ◽  
Vol 63 (12) ◽  
pp. 3991-3999
Author(s):  
Benjamin van der Woerd ◽  
Min Wu ◽  
Vijay Parsa ◽  
Philip C. Doyle ◽  
Kevin Fung

Objectives This study aimed to evaluate the fidelity and accuracy of a smartphone microphone and recording environment on acoustic measurements of voice. Method A prospective cohort proof-of-concept study. Two sets of prerecorded samples (a) sustained vowels (/a/) and (b) Rainbow Passage sentence were played for recording via the internal iPhone microphone and the Blue Yeti USB microphone in two recording environments: a sound-treated booth and quiet office setting. Recordings were presented using a calibrated mannequin speaker with a fixed signal intensity (69 dBA), at a fixed distance (15 in.). Each set of recordings (iPhone—audio booth, Blue Yeti—audio booth, iPhone—office, and Blue Yeti—office), was time-windowed to ensure the same signal was evaluated for each condition. Acoustic measures of voice including fundamental frequency ( f o ), jitter, shimmer, harmonic-to-noise ratio (HNR), and cepstral peak prominence (CPP), were generated using a widely used analysis program (Praat Version 6.0.50). The data gathered were compared using a repeated measures analysis of variance. Two separate data sets were used. The set of vowel samples included both pathologic ( n = 10) and normal ( n = 10), male ( n = 5) and female ( n = 15) speakers. The set of sentence stimuli ranged in perceived voice quality from normal to severely disordered with an equal number of male ( n = 12) and female ( n = 12) speakers evaluated. Results The vowel analyses indicated that the jitter, shimmer, HNR, and CPP were significantly different based on microphone choice and shimmer, HNR, and CPP were significantly different based on the recording environment. Analysis of sentences revealed a statistically significant impact of recording environment and microphone type on HNR and CPP. While statistically significant, the differences across the experimental conditions for a subset of the acoustic measures (viz., jitter and CPP) have shown differences that fell within their respective normative ranges. Conclusions Both microphone and recording setting resulted in significant differences across several acoustic measurements. However, a subset of the acoustic measures that were statistically significant across the recording conditions showed small overall differences that are unlikely to have clinical significance in interpretation. For these acoustic measures, the present data suggest that, although a sound-treated setting is ideal for voice sample collection, a smartphone microphone can capture acceptable recordings for acoustic signal analysis.


1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Celine Larkin ◽  
Alexandra M. Sanseverino ◽  
James Joseph ◽  
Lauren Eisenhauer ◽  
Martin A. Reznek

Abstract Background Audit and feedback (A&F) has been used as a strategy to modify clinician behavior with moderate success. Although A&F is theorized to work by improving the accuracy of clinicians’ estimates of their own behavior, few interventions have included assessment of clinicians’ estimates at baseline to examine whether they account for intervention success or failure. We tested an A&F intervention to reduce computed tomography (CT) ordering by emergency physicians, while also examining the physicians’ baseline estimates of their own behavior compared to peers. Methods Our study was a prospective, multi-site, 20-month, randomized trial to examine the effect of an A&F intervention on CT ordering rates, overall and by test subtype. From the electronic health record, we obtained 12 months of baseline CT ordering per 100 patients treated for every physician from four emergency departments. Those who were randomized to receive A&F were shown a de-identified graph of the group’s baseline CT utilization, asked to estimate wherein the distribution of their own CT order practices fell, and then shown their actual performance. All participants also received a brief educational intervention. CT ordering rates were collected for all physicians for 6 months after the intervention. Pre-post ordering rates were compared using independent and repeated measures t tests. Results Fifty-one of 52 eligible physicians participated. The mean CT ordering rate increased significantly in both experimental conditions after the intervention (intervention pre = 35.7, post = 40.3, t = 4.13, p < 0.001; control pre = 33.9, post = 38.9, t = 3.94, p = 0.001), with no significant between-group difference observed at follow-up (t = 0.43, p = 0.67). Within the intervention group, physicians had poor accuracy in estimating their own ordering behavior at baseline: most overestimated and all guessed that they were in the upper half of the distribution of their peers. CT ordering increased regardless of self-estimate accuracy. Conclusions Our A&F intervention failed to reduce physician CT ordering: our feedback to the physicians showed most of them that they had overestimated their CT ordering behavior, and they were therefore unlikely to reduce it as a result. After “audit,” it may be prudent to assess baseline clinician awareness of behavior before moving toward a feedback intervention.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3441
Author(s):  
Carlos D. Gómez-Carmona ◽  
Sebastián Feu ◽  
José Pino-Ortega ◽  
Sergio J. Ibáñez

The present study analyzed the multi-location external workload profile in basketball players using a previously validated test battery and compared the demands among anatomical locations. A basketball team comprising 13 semi-professional male players was evaluated in five tests (abilities/skills/tests): (a) aerobic, linear movement, 30-15 IFT; (b) lactic anaerobic, acceleration and deceleration, 16.25 m RSA (c) alactic anaerobic, curvilinear movement, 6.75 m arc (d) elastic, jump, Abalakov test (e) physical-conditioning, small-sided game, 10’ 3 vs.3 10 × 15 m. PlayerLoadRT was evaluated at six anatomical locations simultaneously (interscapular line, lumbar region, knees and ankles) by six WIMU PROTM inertial devices attached to the player using an ad hoc integral suit. Statistical analysis was composed of an ANOVA of repeated measures and partial eta squared effect sizes. Significant differences among anatomical locations were found in all tests with higher values in the location nearer to ground contact (p < 0.01). However, differences between lower limb locations were only found in curvilinear movements, with a higher workload in the outside leg (p < 0.01). Additionally, high between-subject variability was found in team players, especially at lower limb locations. In conclusion, multi-location evaluation in sports movements will make it possible to establish an individual external workload profile and design specific strategies for training and injury prevention programs.


2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Christoph A. Schmalhofer ◽  
Peter Griebel ◽  
Manfred Aigner

The use of highly reactive hydrogen-rich fuels in lean premixed combustion systems strongly affects the operability of stationary gas turbines (GT) resulting in higher autoignition and flashback risks. The present study investigates the autoignition behavior and ignition kernel evolution of hydrogen–nitrogen fuel mixtures in an inline co-flow injector configuration at relevant reheat combustor operating conditions. High-speed luminosity and particle image velocimetry (PIV) measurements in an optically accessible reheat combustor are employed. Autoignition and flame stabilization limits strongly depend on temperatures of vitiated air and carrier preheating. Higher hydrogen content significantly promotes the formation and development of different types of autoignition kernels: More autoignition kernels evolve with higher hydrogen content showing the promoting effect of equivalence ratio on local ignition events. Autoignition kernels develop downstream a certain distance from the injector, indicating the influence of ignition delay on kernel development. The development of autoignition kernels is linked to the shear layer development derived from global experimental conditions.


2014 ◽  
Vol 1 (2) ◽  
pp. 140271 ◽  
Author(s):  
Yu Gu ◽  
Ruslan Burtovyy ◽  
John Custer ◽  
Igor Luzinov ◽  
Konstantin G. Kornev

When controlling the assembly of magnetic nanorods and chains of magnetic nanoparticles, it is extremely challenging to bring them together side by side while keeping a desired spacing between their axes. We show that this challenge can be successfully resolved by using a non-uniform magnetic field that defeats an inherent repulsion between nanorods. Nickel nanorods were suspended in a viscous film and a non-uniform field was used to control their placement. The in-plane movement of nanorods was tracked with a high-speed camera and a detailed image analysis was conducted to quantitatively characterize the behaviour of the nanorods. The analysis focused on the behaviour of a pair of neighbour nanorods, and a corresponding dynamic model was formulated and investigated. The complex two-dimensional dynamics of a nanorod pair was analysed analytically and numerically, and a phase portrait was constructed. Using this phase portrait, we classified the nanorod behaviour and revealed the experimental conditions in which nanorods could be placed side by side. Dependence of the distance between a pair of neighbour nanorods on physical parameters was analysed. With the aid of the proposed theory, one can build different lattices and control their spacing by applying different field gradients.


2017 ◽  
Vol 58 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Javier Miñano-Espin ◽  
Luis Casáis ◽  
Carlos Lago-Peñas ◽  
Miguel Ángel Gómez-Ruano

AbstractReal Madrid was named as the best club of the 20th century by the International Federation of Football History and Statistics. The aim of this study was to compare if players from Real Madrid covered shorter distances than players from the opposing team. One hundred and forty-nine matches including league, cup and UEFA Champions League matches played by the Real Madrid were monitored during the 2001-2002 to the 2006-2007 seasons. Data from both teams (Real Madrid and the opponent) were recorded. Altogether, 2082 physical performance profiles were examined, 1052 from the Real Madrid and 1031 from the opposing team (Central Defenders (CD) = 536, External Defenders (ED) = 491, Central Midfielders (CM) = 544, External Midfielders (EM) = 233, and Forwards (F) = 278). Match performance data were collected using a computerized multiple-camera tracking system (Amisco Pro®, Nice, France). A repeated measures analysis of variance (ANOVA) was performed for distances covered at different intensities (sprinting (>24.0 km/h) and high-speed running (21.1-24.0 km/h) and the number of sprints (21.1-24.0 km/h and >24.0 km/h) during games for each player sectioned under their positional roles. Players from Real Madrid covered shorter distances in high-speed running and sprint than players from the opposing team (p < 0.01). While ED did not show differences in their physical performance, CD (p < 0.05), CM (p < 0.01), EM (p < 0.01) and F (p > 0.01) from Real Madrid covered shorter distances in high-intensity running and sprint and performed less sprints than their counterparts. Finally, no differences were found in the high-intensity running and sprint distances performed by players from Real Madrid depending on the quality of the opposition.


Sign in / Sign up

Export Citation Format

Share Document