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Carl Petersen, David B. Pyne, Marc R. Portus, Stuart Karppinen and Brian Dawson

Purpose:

The time-motion characteristics and the within-athlete variability in movement patterns were quantified for the same male fast bowler playing One Day International (ODI) cricket matches (n = 12).

Methods:

A number of different time motion characteristics were monitored using a portable 5-Hz global positioning system (GPS) unit (Catapult, Melbourne, Australia).

Results:

The bowler’s mean workload per ODI was 8 ± 2 overs (mean ± SD). He covered a total distance of 15.9 ± 2.5 km per game; 12 ± 3% or 1.9 ± 0.2 km was striding (0.8 ± 0.2 km) or sprinting (1.1 ± 0.2 km), whereas 10.9 ± 2.1 km was spent walking. One high-intensity (running, striding, or sprinting) repetition (HIR) occurred every 68 ± 12 s, and the average duration of a HI effort was 2.7 ± 0.1 s. The player also completed 66 ± 11 sprints per game; mean sprint distance was 18 ± 3 m and maximum sprinting speed 8.3 ± 0.9 m·s−1.

Conclusions:

The movement patterns of this fast bowler were a combination of highly intermittent activities of variable intensity on the base of ~16 km per game. This information provides insight for conditioning coaches to determine the physical demands and to adapt the training and recovery processes of ODI fast bowlers.

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Sam Coad, Bon Gray, George Wehbe and Christopher McLellan

Purpose:

To examine the response or pre- and postmatch salivary immunoglobulin A concentration ([s-IgA]) to Australian Football League (AFL) match play and investigate the acute and cumulative influence of player workload and postmatch [s-IgA] after repeated participation in AFL match play.

Methods:

Eleven elite AFL athletes (21.8 ± 2.4 y, 186.9 ± 7.9 cm, 87.4 ± 7.5 kg) were monitored throughout 3 matches during the preseason that were separated by 7 d. Saliva samples were collected across each AFL match at 24 h and 1 h prematch and 1, 12, 36, and 60 h postmatch to determine [s-IgA]. Global positioning systems (GPS) with integrated triaxial accelerometers were used to determine total player workload during match play. Hypothesis testing was conducted for time-dependent changes in [s-IgA] and player load using a repeated-measures ANOVA.

Results:

Player load during match 3 (1266 ± 124.6 AU) was significantly (P < .01) greater than in match 1 (1096 ± 115.1 AU) and match 2 (1082 ± 90.4 AU). Across match 3, [s-IgA] was significantly (P < .01) suppressed at 2 postmatch measures (12 and 36 h) compared with prematch measures (24 and 1 h), which coincided with significantly (P < .01) elevated player load.

Conclusion:

The findings indicate that an increase in player load during AFL preseason match play resulted in compromised postmatch mucosal immunological function. Longitudinal assessment of AFL-match player load and mucosal immunological function across the first 60 h of recovery may augment monitoring and preparedness strategies for athletes.

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Luke W. Hogarth, Brendan J. Burkett and Mark R. McKean

Purpose:

To examine the neuromuscular and perceptual fatigue responses to consecutive tag football matches played on the same day and determine the relationship between fatigue and match running performance.

Methods:

Neuromuscular and perceptual fatigue responses of 15 national tag football players were assessed before and during the 2014 State of Origin tournament. Global positioning systems (GPS) provided data on players’ match running performance, and a vertical-jump test and subjective questionnaire were used to assess players’ neuromuscular and perceptual fatigue, respectively.

Results:

There were small to moderate reductions in the majority of match-running-performance variables over consecutive matches, including distance (ES = −0.81), high-speed-running (HSR) distance (ES = −0.51), HSR efforts (ES = −0.64), and maximal accelerations (ES = −0.76). Prematch vertical jump was initially below baseline values before the first match (ES = 0.68−0.88). There were no substantial reductions in vertical-jump performance from baseline values over consecutive matches, although there was a small decline from after match 2 to after match 3 (3.3%; ES = −0.45 ± 0.62). There were progressive reductions in perceived well-being scores after matches 1 (ES = −0.38), 2 (ES = −0.70), and 3 (ES = −1.14). There were small to moderate associations between changes in fatigue measures and match running performance.

Conclusions:

Perceptual fatigue accumulates over consecutive tag football matches, although there were only marginal increases in neuromuscular fatigue. However, both neuromuscular and perceptual fatigue measures were found to contribute to reduced match running performance in the final match.

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Darren Burgess, Geraldine Naughton and Kevin Norton

Purpose:

The understanding of the gap between Under 18 y (U18) and senior-level competition and the evolution of this gap in Australian Football lack a strong evidence base. Despite the multimillion dollars invested in recruitment, scientific research on successful transition is limited. No studies have compared individual players’ movement rate, game statistics and ball speed in U18 and senior competition of the Australian Football League across time. This project compared differences in player movement and ball speed between matches from senior AFL competitive matches and U18 players in the 2003 and 2009 seasons.

Methods:

TrakPerformance Software and Global Positioning System (GPS) technology were used to analyze the movement of players, ball speed and game statistics. ANOVA compared the two levels of competition over time.

Results:

Observed interactions for distance traveled per minute of play (P = .009), number of sprints per minute of play (P < .001), time spent at sprint speed in the game (P < .001), time on field (P < .001), and ball speed (P < .001) were found. Subsequent analysis identified increases in movement patterns in senior AFL competition in 2009 compared with the same level of competition in 2003 and U18 players in 2003 and 2009.

Conclusions:

Senior AFL players in 2009 were moving further, sprinting relatively more frequently, playing less time and playing at game speeds significantly greater than the same senior competition in 2003 as well as compared with both cohorts of U18 players.

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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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Ryu Nagahara, Jean-Benoit Morin and Masaaki Koido

Purpose:

To assess soccer-specific impairment of mechanical properties in accelerated sprinting and its relation with activity profiles during an actual match.

Methods:

Thirteen male field players completed 4 sprint measurements, wherein running speed was obtained using a laser distance-measurement system, before and after the 2 halves of 2 soccer matches. Macroscopic mechanical properties (theoretical maximal horizontal force [F0], maximal horizontal sprinting power [Pmax], and theoretical maximal sprinting velocity [V0]) during the 35-m sprint acceleration were calculated from speed–time data. Players’ activity profiles during the matches were collected using global positioning system units.

Results:

After the match, although F0 and Pmax did not significantly change, V0 was reduced (P = .038), and the magnitude of this reduction correlated with distance (positive) and number (negative) of high-speed running, number of running (negative), and other low-intensity activity distance (negative) during the match. Moreover, Pmax decreased immediately before the second half (P = .014).

Conclusions:

The results suggest that soccer-specific fatigue probably impairs players’ maximal velocity capabilities more than their maximal horizontal force-production abilities at initial acceleration. Furthermore, long-distance running, especially at high speed, during the match may induce relatively large impairment of maximal velocity capabilities. In addition, the capability of producing maximal horizontal power during sprinting is presumably impaired during halftime of a soccer match with passive recovery. These findings could be useful for players and coaches aiming to train effectively to maintain sprinting performance throughout a soccer match when planning a training program.

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Jace A. Delaney, Heidi R. Thornton, Grant M. Duthie and Ben J. Dascombe

Background:

Rugby league coaches adopt replacement strategies for their interchange players to maximize running intensity; however, it is important to understand the factors that may influence match performance.

Purpose:

To assess the independent factors affecting running intensity sustained by interchange players during professional rugby league.

Methods:

Global positioning system (GPS) data were collected from all interchanged players (starters and nonstarters) in a professional rugby league squad across 24 matches of a National Rugby League season. A multilevel mixed-model approach was employed to establish the effect of various technical (attacking and defensive involvements), temporal (bout duration, time in possession, etc), and situational (season phase, recovery cycle, etc) factors on the relative distance covered and average metabolic power (Pmet) during competition. Significant effects were standardized using correlation coefficients, and the likelihood of the effect was described using magnitude-based inferences.

Results:

Superior intermittent running ability resulted in very likely large increases in both relative distance and Pmet. As the length of a bout increased, both measures of running intensity exhibited a small decrease. There were at least likely small increases in running intensity for matches played after short recovery cycles and against strong opposition. During a bout, the number of collision-based involvements increased running intensity, whereas time in possession and ball time out of play decreased demands.

Conclusions:

These data demonstrate a complex interaction of individual- and match-based factors that require consideration when developing interchange strategies, and the manipulation of training loads during shorter recovery periods and against stronger opponents may be beneficial.

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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.

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Brendan R. Scott, Robert G. Lockie, Timothy J. Knight, Andrew C. Clark and Xanne A.K. Janse de Jonge

Purpose:

To compare various measures of training load (TL) derived from physiological (heart rate [HR]), perceptual (rating of perceived exertion [RPE]), and physical (global positioning system [GPS] and accelerometer) data during in-season field-based training for professional soccer.

Methods:

Fifteen professional male soccer players (age 24.9 ± 5.4 y, body mass 77.6 ± 7.5 kg, height 181.1 ± 6.9 cm) were assessed in-season across 97 individual training sessions. Measures of external TL (total distance [TD], the volume of low-speed activity [LSA; <14.4 km/h], high-speed running [HSR; >14.4 km/h], very high-speed running [VHSR; >19.8 km/h], and player load), HR and session-RPE (sRPE) scores were recorded. Internal TL scores (HR-based and sRPE-based) were calculated, and their relationships with measures of external TL were quantified using Pearson product–moment correlations.

Results:

Physical measures of TD, LSA volume, and player load provided large, significant (r = .71−.84; P < .01) correlations with the HR-based and sRPE-based methods. Volume of HSR and VHSR provided moderate to large, significant (r = .40−.67; P < .01) correlations with measures of internal TL.

Conclusions:

While the volume of HSR and VHSR provided significant relationships with internal TL, physical-performance measures of TD, LSA volume, and player load appear to be more acceptable indicators of external TL, due to the greater magnitude of their correlations with measures of internal TL.

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Samuel Ryan, Aaron J. Coutts, Joel Hocking and Thomas Kempton

Purpose:

To examine the influence of a range of individual player characteristics and match-related factors on activity profiles during professional Australian football matches.

Methods:

Global positioning system (GPS) profiles were collected from 34 professional Australian football players from the same club over 15 competition matches. GPS data were classified into relative total and high-speed running (HSR; >20 km/h) distances. Individual player aerobic fitness was determined from a 2-km time trial conducted during the preseason. Each match was classified according to match location, season phase, recovery length, opposition strength, and match outcome. The total number of stoppages during the match was obtained from a commercial statistics provider. A linear mixed model was constructed to examine the influence of player characteristics and match-related factors on both relative total and HSR outputs.

Results:

Player aerobic fitness had a large effect on relative total and HSR distances. Away matches and matches lost produced only small reductions in relative HSR distances, while the number of rotations also had a small positive effect. Matches won, more player rotations, and playing against strong opposition all resulted in small to moderate increases in relative total distance, while early season phase, increased number of stoppages, and away matches resulted in small to moderate reductions in relative total distance.

Conclusions:

There is a likely interplay of factors that influence running performance during Australian football matches. The results highlight the need to consider a variety of contextual factors when interpreting physical output from matches.