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Jace A. Delaney, Grant M. Duthie, Heidi R. Thornton, Tannath J. Scott, David Gay and Ben J. Dascombe

Rugby league involves frequent periods of high-intensity running including acceleration and deceleration efforts, often occurring at low speeds.

Purpose:

To quantify the energetic cost of running and acceleration efforts during rugby league competition to aid in prescription and monitoring of training.

Methods:

Global positioning system (GPS) data were collected from 37 professional rugby league players across 2 seasons. Peak values for relative distance, average acceleration/deceleration, and metabolic power (Pmet) were calculated for 10 different moving-average durations (1–10 min) for each position. A mixed-effects model was used to assess the effect of position for each duration, and individual comparisons were made using a magnitude-based-inference network.

Results:

There were almost certainly large differences in relative distance and Pmet between the 10-min window and all moving averages <5 min in duration (ES = 1.21–1.88). Fullbacks, halves, and hookers covered greater relative distances than outside backs, edge forwards, and middle forwards for moving averages lasting 2–10 min. Acceleration/deceleration demands were greatest in hookers and halves compared with fullbacks, middle forwards, and outside backs. Pmet was greatest in hookers, halves, and fullbacks compared with middle forwards and outside backs.

Conclusions:

Competition running intensities varied by both position and moving-average duration. Hookers exhibited the greatest Pmet of all positions, due to high involvement in both attack and defense. Fullbacks also reached high Pmet, possibly due to a greater absolute volume of running. This study provides coaches with match data that can be used for the prescription and monitoring of specific training drills.

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Mohamed S. Fessi, Fayçal Farhat, Alexandre Dellal, James J. Malone and Wassim Moalla

matches. 10 , 11 Common methods include time–motion analysis (such as video 11 and global positioning systems [GPS]), 12 – 14 heart-rate kinetics, 10 , 15 and rating of perceived exertion (RPE). 10 , 16 Usually, GPS technology is used to measure the distance covered or time spent at different running

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Nick B. Murray, Tim J. Gabbett and Andrew D. Townshend

use Global Positioning System (GPS) technology to provide information on the activity profiles of players during training and compeition. 3 – 5 With the physical demands of AF increasing, 6 it is critical that strength and conditioning staff prescribe an appropriate training stimulus to enhance the

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Dac Minh Tuan Nguyen, Virgile Lecoultre, Yoshiyuki Sunami and Yves Schutz

Background:

Physical activity (PA) and related energy expenditure (EE) is often assessed by means of a single technique. Because of inherent limitations, single techniques may not allow for an accurate assessment both PA and related EE. The aim of this study was to develop a model to accurately assess common PA types and durations and thus EE in free-living conditions, combining data from global positioning system (GPS) and 2 accelerometers.

Methods:

Forty-one volunteers participated in the study. First, a model was developed and adjusted to measured EE with a first group of subjects (Protocol I, n = 12) who performed 6 structured and supervised PA. Then, the model was validated over 2 experimental phases with 2 groups (n = 12 and n = 17) performing scheduled (Protocol I) and spontaneous common activities in real-life condition (Protocol II). Predicted EE was compared with actual EE as measured by portable indirect calorimetry.

Results:

In protocol I, performed PA types could be recognized with little error. The duration of each PA type could be predicted with an accuracy below 1 minute. Measured and predicted EE were strongly associated (r = .97, P < .001).

Conclusion:

Combining GPS and 2 accelerometers allows for an accurate assessment of PA and EE in free-living situations.

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Joel Garrett, Stuart R. Graham, Roger G. Eston, Darren J. Burgess, Lachlan J. Garrett, John Jakeman and Kevin Norton

25-m halfway mark to help control for speed of the run. Average performance across the 3 trials was used as the criterion measure. The GPS-embedded triaxial accelerometers unit was worn in a specialized pocket in the training and match guernsey, located between the scapulae of the participant. For

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Esther Morencos, Blanca Romero-Moraleda, Carlo Castagna and David Casamichana

In recent years, global positioning system (GPS) analysis has become a widely used tool for quantifying competition demands, informing training prescription, and monitoring the training stimulus. 1 In team sports such as hockey, considered as intermittent, high-intensity activity, 2 reductions in

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Cesar Gallo-Salazar, Juan Del Coso, David Sanz-Rivas and Jaime Fernandez-Fernandez

-Eye, 5 or global position systems (GPS) 6 – 11 among the most typically used for these purposes. Quantifying this information during real or simulated tennis matches helps coaches to provide objective knowledge about the demands of match play, ultimately improving the preparation of more effective

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Fergus O’Connor, Heidi R. Thornton, Dean Ritchie, Jay Anderson, Lindsay Bull, Alex Rigby, Zane Leonard, Steven Stern and Jonathan D. Bartlett

also represent a significant risk of soft-tissue injury, particularly if the athlete is not conditioned to undergo maximal sprinting early in the preseason. Developments in commercially available global positioning systems (GPS) allow practitioners to reliably measure maximal velocity when it occurs

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Jonathon J.S. Weakley, Dale B. Read, Hugh H.K. Fullagar, Carlos Ramirez-Lopez, Ben Jones, Cloe Cummins and John A. Sampson

end of each bout) during SSGs has not been assessed. Team sport athletes often wear microtechnology devices that contain a global positioning system (GPS) and inertial sensors during training and match play. 15 – 17 These devices are commonly used to monitor training loads and intensities, with

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Gregory Roe, Joshua Darrall-Jones, Christopher Black, William Shaw, Kevin Till and Ben Jones

Purpose:

The purpose of this study was to investigate the validity of timing gates and 10-Hz global positioning systems (GPS) units (Catapult Optimeye S5) against a criterion measure (50-Hz radar gun) for assessing maximum sprint velocity (Vmax).

Methods:

Nine male professional rugby union players performed 3 maximal 40-m sprints with 3 min rest between efforts with Vmax assessed simultaneously via timing gates, 10-Hz GPSOpen (Openfield software), GPSSprint (Sprint software), and radar gun. Eight players wore 3 GPS units, while 1 wore a single unit during each sprint.

Results:

When compared with the radar gun, mean biases for GPSOpen, GPSSprint, and timing gates were trivial, small, and small, respectively. The typical error of the estimate (TEE) was small for timing gate and GPSOpen while moderate for GPSSprint. Correlations with radar gun were nearly perfect for all measures. Mean bias, TEE, and correlations between GPS units were trivial, small, and nearly perfect, respectively, while a small TEE existed when GPSOpenfield was compared with GPSSprint.

Conclusion:

Based on these findings, both 10-Hz GPS and timing gates provide valid measures of 40-m Vmax assessment compared with a radar gun. However, as error did exist between measures, the same testing protocol should be used when assessing 40-m Vmax over time. Furthermore, in light of the above results, it is recommended that when assessing changes in GPS-derived Vmax over time, practitioners should use the same unit for each player and perform the analysis with the same software, preferably Catapult Openfield.