Caffeine-containing energy drink improves physical performance of elite rugby players during a simulated match

2013 ◽  
Vol 38 (4) ◽  
pp. 368-374 ◽  
Author(s):  
Juan Del Coso ◽  
Juan A. Ramírez ◽  
Gloria Muñoz ◽  
Javier Portillo ◽  
Cristina Gonzalez-Millán ◽  
...  
Keyword(s):  
Physical Performance ◽  
Body Mass ◽  
Global Positioning System ◽  
Energy Drink ◽  
Dose Equivalent ◽  
Caffeine Concentration ◽  
Global Positioning ◽  
The Individual ◽  
Rugby Players ◽  
Simulated Match

The purpose of this study was to investigate the effectiveness of a caffeine-containing energy drink in enhancing rugby players' physical performance during a simulated match. A second purpose was to determine the urinary caffeine excretion derived from the energy drink intake. In a randomized and counterbalanced order, 26 elite rugby players (mean ± SD for age and body mass, 25 ± 2 y and 93 ± 15 kg) played 2 simulated rugby games (2 × 30 min) 60 min after ingesting (i) 3 mg of caffeine per kilogram of body mass in the form of an energy drink (Fure, ProEnergetics) or (ii) the same drink without caffeine (placebo). During the matches, the individual running distance and the instantaneous speed were measured, and the number of running actions above 20 km·h−1 (i.e., sprints) were determined, using global positioning system devices. The number of impacts above 5 g during the matches was determined by accelerometry. The ingestion of the energy drink, compared with the placebo, increased the total distance covered during the match (4749 ± 589 vs 5139 ± 475 m, p < 0.05), the running distance covered at more than 20 km·h−1 (184 ± 38 vs 208 ± 38 m, p < 0.05), and the number of sprints (10 ± 7 vs 12 ± 7, p < 0.05). The ingestion of the energy drink also resulted in a greater overall number of impacts (481 ± 352 vs 641 ± 366, p < 0.05) and a higher postexercise urine caffeine concentration (0.1 ± 0.1 vs 2.4 ± 0.9 μg·mL−1, p < 0.05). The use of an energy drink with a caffeine dose equivalent to 3 mg·kg−1 considerably enhanced the movement patterns of rugby players during a simulated match.

Monitoring Players’ Readiness Using Predicted Heart-Rate Responses to Soccer Drills

2018 ◽  
Vol 13 (10) ◽  
pp. 1273-1280 ◽  
Author(s):  
Mathieu Lacome ◽  
Ben Simpson ◽  
Nick Broad ◽  
Martin Buchheit
Keyword(s):  
Heart Rate ◽  
Global Positioning System ◽  
Daily Basis ◽  
Internal Load ◽  
Individual Level ◽  
Multiple Stepwise Regression Analysis ◽  
Global Positioning ◽  
Fitness Criterion ◽  
The Difference ◽  
The Individual

Purpose: To examine the ability of multivariate models to predict the heart-rate (HR) responses to some specific training drills from various global positioning system (GPS) variables and to examine the usefulness of the difference in predicted vs actual HR responses as an index of fitness or readiness to perform. Method: All data were collected during 1 season (2016–17) with players’ soccer activity recorded using 5-Hz GPS and internal load monitored using HR. GPS and HR data were analyzed during typical small-sided games and a 4-min standardized submaximal run (12 km·h−1). A multiple stepwise regression analysis was used to identify which combinations of GPS variables showed the largest correlations with HR responses at the individual level (HRACT, 149 [46] GPS/HR pairs per player) and was further used to predict HR during individual drills (HRPRED). Then, HR predicted was compared with actual HR to compute an index of fitness or readiness to perform (HRΔ, %). The validity of HRΔ was examined while comparing changes in HRΔ with the changes in HR responses to a submaximal run (HRRUN, fitness criterion) and as a function of the different phases of the season (with fitness being expected to increase after the preseason). Results: HRPRED was very largely correlated with HRACT (r = .78 [.04]). Within-player changes in HRΔ were largely correlated with within-player changes in HRRUN (r = .66, .50–.82). HRΔ very likely decreased from July (3.1% [2.0%]) to August (0.8% [2.2%]) and most likely decreased further in September (−1.5% [2.1%]). Conclusions: HRΔ is a valid variable to monitor elite soccer players’ fitness and allows fitness monitoring on a daily basis during normal practice, decreasing the need for formal testing.

Analysis of Physical Collisions in Elite National Rugby League Match Play

2015 ◽  
Vol 10 (6) ◽  
pp. 732-739 ◽  
Author(s):  
Cloe Cummins ◽  
Rhonda Orr
Keyword(s):  
Global Positioning System ◽  
Rugby League ◽  
Positioning System ◽  
Match Play ◽  
Impact Forces ◽  
Global Positioning ◽  
The Individual ◽  
Attack And Defense ◽  
The Impact

Objective: To investigate the impact forces of collision events during both attack and defense in elite rugby league match play and to compare the collision profiles between playing positions. Participants: 26 elite rugby league players. Methods: Player collisions were recorded using an integrated accelerometer in global positioning system units (SPI-Pro X, GPSports). Impact forces of collisions in attack (hit-ups) and defense (tackles) were analyzed from 359 files from outside backs (n = 78), adjustables (n = 97), wide-running forwards (n = 136), and hit-up forwards (n = 48) over 1 National Rugby League season. Results: Hit-up forwards were involved in 0.8 collisions/min, significantly more than all other positional groups (wide-running forwards P = .050, adjustables P = .042, and outside backs P = .000). Outside backs experienced 25% fewer collisions per minute than hit-up forwards. Hit-up forwards experienced a collision within the 2 highest classifications of force (≥10 g) every 2.5 min of match play compared with 1 every 5 and 9 min for adjustables and outside backs, respectively. Hit-up forwards performed 0.5 tackles per minute of match play, 5 times that of outside backs (ES = 1.90; 95% CI [0.26,3.16]), and 0.2 hit-ups per minute of match play, twice as many as adjustables. Conclusions: During a rugby league match, players are exposed to a significant number of collision events. Positional differences exist, with hit-up and wide-running forwards experiencing greater collision events than adjustables and outside backs. Although these results may be unique to the individual team’s defensive- and attacking-play strategies, they are indicative of the significant collision profiles in professional rugby league.

scholarly journals AGGREGATION OF Hotothuria (Metriatyla) albivenfer SEMPER (1868) (ESHIN9DERMATA: ASPIDOGHIROTIDA) ON SEAGRASS AREA OF MEDANA BAY WEST LOMBOK

2017 ◽  
Vol 14 (1) ◽  
pp. 37
Author(s):  
Pradina Purwati ◽  
Pitra Widianwary ◽  
Sigit Anggoro Putro Dwiono ◽  
Oktavianto Samir
Keyword(s):  
Distribution Pattern ◽  
Global Positioning System ◽  
Mapping Technique ◽  
Positioning System ◽  
Local Distribution ◽  
Individual Number ◽  
Global Positioning ◽  
The Individual

Mapping technique has not been popular in holothurian monitoring procedures. We introduced the use of global positioning system to determine the local distribution pattern and estimate the individual number of Holothuria albiventer al Medana Bay, West Lombok, Indonesia.

Understanding the Components of Information Privacy Threats for Location-Based Services

2014 ◽  
Vol 28 (1) ◽  
pp. 227-242 ◽  
Author(s):  
Robyn L. Raschke ◽  
Anjala S. Krishen ◽  
Pushkin Kachroo
Keyword(s):  
Global Positioning System ◽  
Individual Component ◽  
Information Privacy ◽  
Location Based Services ◽  
Privacy Threats ◽  
Risk Beliefs ◽  
Global Positioning ◽  
Multiple Services ◽  
The Individual ◽  
The Impact

ABSTRACTGiven the increase in global positioning system enabled devices and the ubiquitous ability to connect wirelessly to information through location-based services, organizations are challenged to offer privacy-by-design support systems. Given this, we offer a conceptual framework to capture the impact of the individual component weights of concern for information privacy on behavioral intent of disclosing information. Through a sample of 217 respondents, our PLS model shows that privacy protection beliefs negatively impact concern for collection, unauthorized use, and improper access of information and that privacy risk beliefs positively impact concern for collection and existence of errors; additionally, concern for collection negatively impacts behavioral intentions to disclose information, as does concern for unauthorized use. With such detailed information, firms can address both cognitive and affective consumer concerns, enhance transparency, and communicate multiple services while handling privacy controls as an extension of those services.

A Comparison of the Match Demands of International and Provincial Rugby Sevens

2015 ◽  
Vol 10 (6) ◽  
pp. 786-790 ◽  
Author(s):  
Alex Ross ◽  
Nicholas D. Gill ◽  
John B. Cronin
Keyword(s):  
Global Positioning System ◽  
Video Analysis ◽  
High Speed ◽  
System Analysis ◽  
Positioning System ◽  
Global Positioning ◽  
Technical Factors ◽  
The Individual ◽  
Very High

Purpose: To compare the running demands and match activity profiles of international and provincial rugby sevens players. Participants: 84 rugby sevens players, consisting of 16 international players from 1 team and 68 provincial players from 8 teams. Methods: Global positioning system analysis was completed during international and provincial tournament matches. Video analysis was also used to quantify the individual match activities during tournament matches. Results: Trivial to moderate differences were found in the running demands of international and provincial players, with internationals covering a greater distance at very high speed (ES = 0.30) and performing a greater number of sprints (ES = 0.80). Small differences were found between the 2 levels in all but total tackles (ES = 0.07) and defensive ruck effectiveness (ES = 0.64). International matches incurred a greater overall ball-in-play time than provincial matches (proportion ratio = 1.32). Conclusions: These findings demonstrate that both physical and technical factors distinguish international and provincial rugby sevens, although overall match demands are similar.

scholarly journals Physical and Tactical Demands of the Goalkeeper in Football in Different Small-Sided Games

Sensors ◽  
2019 ◽  
Vol 19 (16) ◽  
pp. 3605 ◽  
Author(s):  
Daniel Jara ◽  
Enrique Ortega ◽  
Miguel-Ángel Gómez-Ruano ◽  
Matthias Weigelt ◽  
Brittany Nikolic ◽  
...  
Keyword(s):  
Physical Performance ◽  
Global Positioning System ◽  
Positioning System ◽  
Physical Demands ◽  
Small Pitch ◽  
Global Positioning ◽  
Spatial Exploration ◽  
Performance Results ◽  
Ellipse Area ◽  
Positional Data

Background: Several studies have examined the differences between the different small-sided game (SSG) formats. However, only one study has analysed how the different variables that define SSGs can modify the goalkeeper’s behavior. The aim of the present study was to analyze how the modification of the pitch size in SSGs affects the physical demands of the goalkeepers. Methods: Three professional male football goalkeepers participated in this study. Three different SSG were analysed (62 m × 44 m for a large pitch; 50 m × 35 m for a medium pitch and 32 m × 23 m for a small pitch). Positional data of each goalkeeper was gathered using an 18.18 Hz global positioning system. The data gathered was used to compute players’ spatial exploration index, standard ellipse area, prediction ellipse area The distance covered, distance covered in different intensities and accelerations/decelerations were used to assess the players’ physical performance. Results and Conclusions: There were differences between small and large SSGs in relation to the distances covered at different intensities and pitch exploration. Intensities were lower when the pitch size was larger. Besides that, the pitch exploration variables increased along with the increment of the pitch size.

An Enhanced Web Based Attendance Application Using Global Positioning System and Face Recognition

2020 ◽  
Vol 17 (8) ◽  
pp. 3344-3348
Author(s):  
J. Jabez ◽  
V. Keerthanaa ◽  
V. Kaviya ◽  
S. Gowri
Keyword(s):  
Face Recognition ◽  
Global Positioning System ◽  
Positioning System ◽  
Extended Time ◽  
Monthly Report ◽  
Web Based ◽  
Global Positioning ◽  
The Individual ◽  
User Friendly

The fashion of sustaining faculty attendance each day is one significant fundamental task in all institutions. The likelihood of having a fallacy, being tampered amidst for parsimonious reasons transpires further great while handling mythical ways of managing attendance. That embeds the institution at the hazard, comprising abrupt efficient, furthermore even restricting the individual interruption in data. Besides, using a biometric mechanism engrosses more extended time plus subsistence of the design is too unusual. To complete with this wearisome process, we purpose to design a Web-based application that includes locating GPS coordinates also facial id based upon front-facing cameras concerning registering the attendance of the student which performs the method simple plus more productive. Google GPS API and camera API that exists in this application to permit the application increased flawless. The user’s attendance is verified based upon the GPS location and camera API. Also, the permission is done with facial ID via face recognition. This system necessity is sensitive to the campus location, i.e., except authorized admin, that should not operate in areas outside the institution plant. A database is used to hold track of all the user’s attendance data. The application is a user-friendly UI in which the admin can analyze the detailed reports of all the users. A monthly report of a user can be downloaded by them during the next day’s entry of their attendance. The application is capable of generating daily, monthly and yearly reports of all users. That, we intend to create alternative attendance system for organizations.

Enhancing Physical Performance in Male Volleyball Players with a Caffeine-Containing Energy Drink

2014 ◽  
Vol 9 (6) ◽  
pp. 1013-1018 ◽  
Author(s):  
Juan Del Coso ◽  
Alberto Pérez-López ◽  
Javier Abian-Vicen ◽  
Juan Jose Salinero ◽  
Beatriz Lara ◽  
...  
Keyword(s):  
Physical Performance ◽  
Body Mass ◽  
Energy Drink ◽  
Scientific Data ◽  
Caffeine Intake ◽  
Double Blind ◽  
Jump Test ◽  
Volleyball Players ◽  
Randomized Experimental Design ◽  
Placebo Drink

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.

scholarly journals Position Specific Running Performances in Professional Football (Soccer): Influence of Different Tactical Formations

Sports ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 161
Author(s):  
Toni Modric ◽  
Sime Versic ◽  
Damir Sekulic
Keyword(s):  
Body Mass ◽  
Analysis Of Variance ◽  
Global Positioning System ◽  
High Intensity ◽  
Training Programs ◽  
Body Height ◽  
Football Players ◽  
Positioning System ◽  
Professional Football ◽  
Global Positioning

Running performances (RPs) are known to be important parameters of success in football (soccer), but there is a lack of studies where RPs are contextualized regarding applied tactical solutions. This study aims to quantify and analyze the differences in position-specific RPs in professional football, when games are played with three defensive players (3DP) and four defensive players (4DP). The participants here include professional football players (M ± SD, age 23.57 ± 2.84 years, body height 181.9 ± 5.17 cm, body mass 78.36 ± 4.18 kg) playing at the highest competitive level in Croatia. RPs were measured by global positioning system and classified into four groups based on playing positions: central defenders (CD; n = 47), wide defenders (WD; n = 24), midfielders (MF; n = 48), or forwards (FW; n = 19). Analysis of variance and discriminant canonical analysis are used to identify differences between 3DP and 4DP tactical solutions in terms of the RPs for each playing position. The number of accelerations and decelerations most significantly contributed to the differentiation of 3DP and 4DP among MFs (Wilks λ = 0.31, p < 0.001), with higher occurrences with 3DP. For CDs, total distance, and high-intensity running were higher in 3DP (Wilks λ = 0.66, p < 0.001). No multivariate differences were found for FW and WD players in terms of the RPs between 3DP and 4DP tactical formations. The characteristics and differences shown in this study may provide useful information for coaching staff regarding changing in-season tactical formations. Additionally, the results are useful for optimizing training programs for football players with different playing positions. When changing from 4DP to 3DP tactical formations, WDs training programs should include more of high-intensity running, while MFs training programs should be more based on short intensity activities (accelerations and decelerations).

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