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Effects of Physical, Technical, and Tactical Factors on Final Ladder Position in Semiprofessional Rugby League

Tim J. Gabbett

Purpose:

A limitation of most rugby league time–motion studies is that researchers have examined the demands of single teams, with no investigations of all teams in an entire competition. This study investigated the activity profiles and technical and tactical performances of successful and less-successful teams throughout an entire rugby league competition.

Methods:

In total, 185 rugby league players representing 11 teams from a semiprofessional competition participated in this study. Global positioning system analysis was completed across the entire season. Video footage from individual matches was also coded via notational analysis for technical and tactical performance of teams.

Results:

Trivial to small differences were found among Top 4, Middle 4, and Bottom 4 teams for absolute and relative total distances covered and distances covered at low speeds. Small, nonsignificant differences (P = .054, ES = 0.31) were found between groups for the distance covered sprinting, with Top 4 teams covering greater sprinting distances than Bottom 4 teams. Top 4 teams made more meters in attack and conceded fewer meters in defense than Bottom 4 teams. Bottom 4 teams had a greater percentage of slow play-the-balls in defense than Top 4 teams (74.8% ± 7.3% vs 67.2% ± 8.3%). Middle 4 teams showed the greatest reduction in high-speed running from the first to the second half (–20.4%), while Bottom 4 teams completed 14.3% more high-speed running in the second half than in the first half.

Conclusion:

These findings demonstrate that a combination of activity profiles and technical and tactical performance are associated with playing success in semiprofessional rugby league players.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 9 (2014): Issue 4 (Jul 2014)

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Predictors of Repeated High-Intensity-Effort Ability in Rugby League Players

Tim J. Gabbett and Aaron J. Wheeler

Purpose:

To investigate the relationship between repeated high-intensity-effort (RHIE) ability and selected physical qualities in rugby league players.

Methods:

Sixteen rugby league players underwent measurements of upper-body strength (4-repetition-maximum [4RM] bench press, weighted chin-up, weighted dips), upper-body muscle endurance (body-mass maximum-repetition chin-up, body-mass maximum-repetition dips), lower-body strength (4RM squat), estimated maximal aerobic power (multistage fitness test), and RHIE ability. The RHIE-ability test consisted of 1 × 10-m sprint, 3 × full-contact 1-on-1 tackling efforts, and a 30-m jog recovery. Players performed 4 repetitions of the test, with each repetition completed in 40 second. During the RHIE test, player speed was evaluated with a 10-m sprint effort while the movement of players was recorded using a wearable microtechnology device. 2D Player Load was used to quantify the collision component of the test.

Results:

Speed decrement was lower for the first- (−2.4% ± 1.0%) than the second-grade (−4.7% ± 2.1%) players. Players with greater initial speed had a higher average speed over the 4 sprints (r = .75), while players with greater maximum-repetition dips maintained a higher 2D Player Load (r = .76).

Conclusions:

These findings demonstrate a relationship between well-developed acceleration and upper-body muscle-endurance qualities and RHIE ability in rugby league players. Training programs designed to develop acceleration and upper-body muscle endurance are likely to improve RHIE ability.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 10 (2015): Issue 6 (Sep 2015)

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Repeated High-Intensity-Effort Activity in Elite and Semielite Rugby League Match Play

Georgia M. Black and Tim J. Gabbett

Purpose:

No study has investigated the frequency and nature of repeated high-intensity-effort (RHIE) bouts across elite and semielite rugby league competitions. This study examined RHIE activity in rugby league match play across playing standards.

Participants:

36 elite and 64 semielite rugby league players.

Methods:

Global positioning system analysis was completed during 17 elite and 14 semielite matches.

Results:

The most commonly occurring RHIE bouts involved 2 efforts (2-RHIE) for both elite and semielite players. Only small differences were found in 2-RHIE activity between elite and semielite match play (effect size [ES] ≥0.31 ± 0.15, ≥88%, likely). RHIE bouts were more likely to involve contact as the number of efforts in a bout increased (ES ≥0.40 ± 0.15, 100%, almost certainly). Semielite players performed a greater proportion of 2-contact-effort RHIE bouts than their elite counterparts (68.2% vs 60.6%, ES 0.33 ± 0.15, 92%, likely), while elite players performed a greater proportion of 3-effort bouts (26.9% vs 21.1%, ES 0.31 ± 0.15, 88%, likely). Elite players also had a shorter recovery (1.00−3.99 vs ≥4.00 min) between RHIE bouts (ES ≥1.60 ± 0.71, ≥94%, likely).

Conclusion:

These findings highlight the RHIE demands of elite and semielite rugby league match play. Elite players are more likely to perform RHIE bouts consisting of 3 efforts and to have a shorter recovery time between bouts. Exposing players to these RHIE demands in training is likely to improve their ability to tolerate the most demanding passages of match play.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 10 (2015): Issue 6 (Sep 2015)

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Repeated High-Intensity-Effort Activity in Relation to Tries Scored and Conceded During Rugby League Match Play

Tim J. Gabbett and Caleb W. Gahan

Purpose:

To examine the nature and frequency of rugby league repeated high-intensity-effort (RHIE) activity in relation to tries scored and conceded in successful and unsuccessful teams.

Participants:

185 semiprofessional rugby league players (mean ± SD age 23.7 ± 3.2 y) from 11 teams.

Methods:

Global positioning system (GPS) data were collected during 21 matches and analyzed for the total number of RHIE bouts, efforts per bout, duration of efforts, and recovery between efforts. Using notational analysis, a RHIE-bout frequency distribution, representing 0–60 s, 61–120 s, 121–180 s, 181–240 s, and 241–300 s before scoring and conceding a try, was established.

Results:

Over 50% of RHIE bouts occurred within 5 min of a try. Bottom-4 teams performed a greater proportion of bouts within 5 min of a try than top-4 teams (61.5% vs 48.2%, effect size, ES = 0.69 ± 0.28, P = .0001). Top-4 teams performed a greater number of RHIE bouts per conceded try (3.0 ± 2.1 vs 1.6 ± 0.7, ES = 0.74 ± 0.51, P < .05), while bottom-4 teams performed a greater number of RHIE bouts per try scored (3.6 ± 2.5 vs 2.1 ± 1.7, ES = 0.70 ± 0.71, P = .10).

Conclusion:

The majority of rugby league RHIE bouts occur at critical periods during match play. Successful rugby league teams perform more RHIE bouts before conceding tries, while unsuccessful teams perform more bouts before scoring tries. These findings demonstrate that unsuccessful teams are required to work harder to score tries while successful teams work harder to prevent tries.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 11 (2016): Issue 4 (May 2016)

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Two Training-Load Paradoxes: Can We Work Harder and Smarter, Can Physical Preparation and Medical Be Teammates?

Tim J. Gabbett and Rod Whiteley

The authors have observed that in professional sporting organizations the staff responsible for physical preparation and medical care typically practice in relative isolation and display tension as regards their attitudes toward training-load prescription (much more and much less training, respectively). Recent evidence shows that relatively high chronic training loads, when they are appropriately reached, are associated with reduced injury risk and better performance. Understanding this link between performance and training loads removes this tension but requires a better understanding of the relationship between the acute:chronic workload ratio (ACWR) and its association with performance and injury. However, there remain many questions in the area of ACWR, and we are likely at an early stage of our understanding of these parameters and their interrelationships. This opinion paper explores these themes and makes recommendations for improving performance through better synergies in support-staff approaches. Furthermore, aspects of the ACWR that remain to be clarified—the role of shared decision making, risk:benefit estimation, and clearer accountability—are discussed.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 12 (2017): Issue s2 (Apr 2017)

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The Development of a Standardized Skill Assessment for Junior Volleyball Players

Tim J. Gabbett and Boris Georgieff

Purpose:

To develop a skill assessment for junior volleyball players and to evaluate the reliability, validity, and sensitivity of the test for detecting training-induced improvements in skill.

Methods:

Thirty junior volleyball players (mean ± SD age, 15.5 ± 1.0 years) participated in this study. Subjects performed tests of spiking, setting, serving, and passing skills on 2 separate occasions to determine test–retest reliability of accuracy. Two expert coaches evaluated the players’ technique and reevaluated it 1 month after the initial evaluation to determine the intratester reliability for technique measurements. A third expert coach determined the intertester reliability for technique measurements. The validity of the test to discriminate players of different playing abilities was evaluated by testing junior national, state, and novice volleyball players. Finally, each player participated in an 8-week skill-based training program.

Results:

Accuracy measurements and intratester and intertester ratings of players’ technique proved to be highly reproducible (intraclass correlation coefficient, r, .85 to .98, range of typical error of measurement 0.2% to 10.0%). A progressive improvement in skill was observed with increases in playing level, while training-induced improvements were present in all skill tasks.

Conclusions:

These results demonstrate that skill-based testing offers a reliable method of quantifying development and progress in junior volleyball players. In addition, the skill-testing battery was useful in successfully discriminating playing ability among junior volleyball players of varying levels, and it was sensitive to changes in skill with training. These fi ndings demonstrate that skill-based testing is useful for monitoring the development of junior volleyball players.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 1 (2006): Issue 2 (Jun 2006)

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Influence of Prior Knowledge of Exercise Duration on Pacing Strategies During Game-Based Activities

Tim J. Gabbett, Ben Walker, and Shane Walker

Purpose:

To investigate the influence of prior knowledge of exercise duration on the pacing strategies employed during gamebased activities.

Methods:

Twelve semiprofessional team-sport athletes (mean ± SD age 22.8 ± 2.1 y) participated in this study. Players performed 3 small-sided games in random order. In one condition (Control), players were informed that they would play the small-sided game for 12 min and then completed the 12-min game. In a 2nd condition (Deception), players were told that they would play the small-sided game for 6 minutes, but after completing the 6-min game, they were asked to complete another 6 min. In a 3rd condition (Unknown), players were not told how long they would be required to play the small-sided game, but the activity was terminated after 12 min. Movement was recorded using a GPS unit sampling at 10 Hz. Post hoc inspection of video footage was undertaken to count the number of possessions and the number and quality of disposals.

Results:

Higher initial intensities were observed in the Deception (130.6 ± 3.3 m/min) and Unknown (129.3 ± 2.4 m/min) conditions than the Control condition (123.3 ± 3.4 m/min). Greater amounts of high-speed running occurred during the initial phases of the Deception condition, and more low-speed activity occurred during the Unknown condition. A moderately greater number of total skill involvements occurred in the Unknown condition than the Control condition.

Conclusions:

These findings suggest that during game-based activities, players alter their pacing strategy based on the anticipated endpoint of the exercise bout.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 10 (2015): Issue 3 (Apr 2015)

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Repeated High-Intensity Running and Sprinting in Elite Women’s Soccer Competition

Tim J. Gabbett, Håvard Wiig, and Matt Spencer

Background:

To the authors’ knowledge, no study has investigated the concurrent repeated, high-intensity (RHIA) and repeated-sprint activity (RSA) of intermittent team-sport competition.

Purpose:

In this study, they report on the RSA of elite women’s football competition. In addition, they describe the nature of RHIA (eg, striding and sprinting activities) that involve a high energy cost and are associated with short (ie, ≤20 s) recovery periods.

Methods:

Thirteen elite women soccer players underwent video-based time–motion analysis on 34 occasions during national and international standard matches. RSA and RHIA were defined as successive (ie, 2) sprints or striding and sprinting efforts that occurred with ≤20 s between efforts.

Results:

The number of RSA and RHIA bouts performed was similar between the first and second halves of matches. Sprinting and striding/sprinting durations tended to remain relatively stable irrespective of the number of efforts in an RSA or RHIA bout or the period of play. However, recovery duration between efforts increased in the second half, when a greater number of efforts were performed per bout.

Conclusion:

These findings suggest that first- to second-half reductions in RHIA and RSA do not occur in elite women’s soccer competition. However, players increase the amount of low-intensity recovery undertaken between RHIA and RSA efforts, most likely in an attempt to maintain RHIA and RSA performance. These findings emphasize the importance of RSA and RHIA to elite women’s soccer and highlight the importance of training this quality to prevent reductions in performance during competitive match play.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 8 (2013): Issue 2 (Mar 2013)

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The Relationship Between Variables in Wearable Microtechnology Devices and Cricket Fast-Bowling Intensity

Dean J. McNamara, Tim J. Gabbett, Peter Blanch, and Luke Kelly

To date, the monitoring of fast-bowling workloads across training and competition environments has been limited to counting total balls bowled. However, bowling at faster velocities is likely to require greater effort while also placing greater load on the bowler. This study investigated the relationship between prescribed effort and microtechnology outputs in fast bowlers to ascertain whether the technology could provide a more refined measure of workload. Twelve high-performing fast bowlers (mean ± SD age 20.3 ± 2.2 y) participated in the study. Each bowler bowled 6 balls at prescribed bowling intensities of 60%, 70%, 85%, and 100%. The relationships between microtechnology outputs, prescribed intensity, and ball velocity were determined using polynomial regression. Very large relationships were observed between prescribed effort and ball velocity for peak PlayerLoad™ (R = .83 ± .19 and .82 ± .20). The PlayerLoad across lower ranges of prescribed effort exhibited a higher coefficient of variation (CV) (60% = 19.0% [17.0–23.0%]), while the CV at higher ranges of prescribed effort was lower (100% = 7.3% [6.4–8.5%]). Routinely used wearable microtechnology devices offer opportunities to examine workload and intensity in cricket fast bowlers outside the normal metrics reported. They offer a useful tool for prescribing and monitoring bowling intensity and workload in elite fast bowlers.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 13 (2018): Issue 2 (Feb 2018)

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The Use of Relative Speed Zones in Australian Football: Are We Really Measuring What We Think We Are?

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

Objectives: To examine the difference between absolute and relative workloads, injury likelihood, and the acute:chronic workload ratio (ACWR) in elite Australian football. Design: Single-cohort, observational study. Methods: Forty-five elite Australian football players from 1 club participated. Running workloads of players were tracked using Global Positioning System technology and were categorized using either (1) absolute, predefined speed thresholds or (2) relative, individualized speed thresholds. Players were divided into 3 equal groups based on maximum velocity: (1) faster, (2) moderate, or (3) slower. One- and 4-wk workloads were calculated, along with the ACWR. Injuries were recorded if they were noncontact in nature and resulted in “time loss.” Results: Faster players demonstrated a significant overestimation of very high-speed running (HSR) when compared with their relative thresholds (P = .01; effect size = −0.73). Similarly, slower players demonstrated an underestimation of high-(P = .06; effect size = 0.55) and very-high-speed (P = .01; effect size = 1.16) running when compared with their relative thresholds. For slower players, (1) greater amounts of relative very HSR had a greater risk of injury than less (relative risk [RR] = 8.30; P = .04) and (2) greater absolute high-speed chronic workloads demonstrated an increase in injury likelihood (RR = 2.28; P = .16), whereas greater relative high-speed chronic workloads offered a decrease in injury likelihood (RR = 0.33; P = .11). Faster players with a very-high-speed ACWR of >2.0 had a greater risk of injury than those between 0.49 and 0.99 for both absolute (RR = 10.31; P = .09) and relative (RR = 4.28; P = .13) workloads. Conclusions: The individualization of velocity thresholds significantly alters the amount of very HSR performed and should be considered in the prescription of training load.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 13 (2018): Issue 4 (Apr 2018)