Study Notes on Speed, Change of Direction Speed, and Reactive Agility of Rugby League Players

SPEED, CHANGE OF DIRECTION SPEED, AND REACTIVE AGILITY OF RUGBY LEAGUE PLAYERS

AUTHORS

  • Tim J. Gabbett, Brisbane Broncos Rugby League Football Club, Brisbane, Australia

  • Jason N. Kelly, Runaway Bay Rugby League Football Club, Gold Coast, Australia

  • Jeremy M. Sheppard, Australian Institute of Sport, Canberra, Australia

ABSTRACT

Studies have explored speed and change of direction speed in rugby league players; however, none have examined their reactive agility. This study aimed to investigate various speed, change of direction speed, and reactive agility tests to determine their efficacy in discriminating skill levels among players and the relationships among these attributes.

  • Sample: 42 rugby league players

  • Tests Administered: 5 m, 10 m, and 20 m sprints; 'L' run; 505 test; modified 505 test; reactive agility.

  • Findings:
      - First grade players (N=12) had superior sprinting and movement times compared to second grade players (N=30).
      - No significant difference was found in change of direction speed between the two groups.
      - Reactive agility movement times correlated with sprint times but showed no significant relationships with decision time and response accuracy.

  • Conclusion: Reactive agility tests are crucial in assessing perceptual skills, raising questions about the validity of traditional change of direction speed tests.

KEY WORDS

anticipation, decision-making, speed, agility, change of direction speed

INTRODUCTION

Rugby league is a collision sport played globally, characterized by intense physical demands and the need for various physical and tactical skills. Players must possess agility, strength, and the ability to react under pressure. Several agility tests have been used in research, including the 'L' run, 505 test, and Illinois agility run. However, many of these tests rely on preplanned movements, limiting their effectiveness in evaluating real-game performance.   

  • Current Knowledge Gaps:
      - Prior studies have shown limited utility in distinguishing players by position using traditional agility tests.   - There is a lack of research on reactive agility in the context of rugby league.

Sheppard and Young defined agility as "a rapid, whole-body change of direction or speed in response to a sport-specific stimulus." Reactive agility tests, which assess athletes’ ability to respond to unpredictable cues, have demonstrated utility in differentiating skill levels in other sports, suggesting they may do the same for rugby league players.

STUDY OBJECTIVES

  1. To examine a range of speed, change of direction speed, and reactive agility tests commonly used in rugby league to identify effective discrimination between skill levels.

  2. To determine the test-retest reliability of these performance metrics.

  3. To explore the interrelationships among speed, change of direction speed, and reactive agility in rugby league players.

METHODS

Experimental Design

The study implemented a cross-sectional design, comparing first grade and second grade rugby league players using Pearson product moment correlation coefficients to assess relationships among performance metrics.

Subjects
  • Participants: 42 rugby league players (mean age: 23.6 ± 5.3 years) from a premier Gold Coast Rugby League club.

  • Conditioning: All players had completed a 4-month pre-season conditioning program.

  • Consent: Informed consent was obtained from all participants.

Tested Metrics
Speed
  • Running speed evaluated through 5 m, 10 m, and 20 m sprints using dual beam electronic timing gates.

  • Measurement: Time to nearest 0.01 seconds with the fastest of three attempts recorded.

Change of Direction Speed
  • Evaluated through three tests:
      1. 'L' Run: 3 cones arranged in an L shape, measuring fastest time over three attempts.
      2. 505 Test: Involves sprinting, pivoting, and returning through timing gates.   3. Modified 505 Test: Same as the 505, but starting 5 m from timing gates;   fastest time from three trials recorded for all tests.

Reactive Agility Test
  • Participants began on a marked line with timing gates positioned at 5 m left and right and 2 m ahead of the start line.

  • The tester randomly prompted movements, simulating game-like stimuli.

  • Cues: 4 scenarios including varying foot movements directed by the tester, with 8 trials recorded.

  • Scoring: Mean of trials recorded to assess speed and decision time via high-speed video footage.

Statistical Analyses
  • Reliability of tests evaluated using intraclass correlation coefficients (ICC) and typical error measurements (TE).

  • Differences between player grades assessed via independent t-test and Cohen's effect size (ES).

  • Statistical significance set at P ≤ 0.05.

RESULTS

Test-Retest Reliability

Reliability statistics indicated ICCs for sprinting speed were between 0.84 and 0.96, while TE ranged from 1.3% to 3.2%.

  • All agility tests exhibited high reliability, with movement, decision times, and response accuracy on the reactive agility test also being reproducible.

Grade Performance Comparison
  • 5 m Sprint:
      - First Grade: 1.14 ± 0.06 s
      - Second Grade: 1.20 ± 0.11 s
      - Significant difference, moderate effect size (ES = 0.68).

  • 10 m Sprint:
      - First Grade: 1.90 ± 0.09 s
      - Second Grade: 2.00 ± 0.14 s
      - Significant difference, large effect size (ES = 0.85).

  • 20 m Sprint:
      - First Grade: 3.25 ± 0.16 s
      - Second Grade: 3.39 ± 0.21 s
      - Significant difference, large effect size (ES = 0.75).

  • Change of Direction Speed
      - No significant differences found in 505 Test, Modified 505 Test, and 'L' Run for both grades.

Reactive Agility
  • Movement time and decision time on the reactive agility test significantly different for first grade players, suggesting superior anticipatory skills compared to second grade players.

DISCUSSION

The goals of this study were met, confirming that while change of direction speed tests may mirror match-play dynamics, they do not reliably distinguish between player competence.

  • Reactive agility revealed faster movement and decision times for higher skilled players without sacrificing accuracy, illustrating its utility in assessing perceptual agility.

  • Findings underline a necessity for rugby league coaches to critically assess the appropriateness of traditional change of direction speed tests in player evaluations.

Practical Applications

This study establishes the imperative to incorporate reactive agility evaluations in rugby league training regimes as they effectively highlight perceptual skill disparities among players. Coaches should recognize the limitations of current agility tests and focus on developing drills that enhance decision-making capabilities potentially through video or in-game scenarios.

TABLES

Table 1

Test-Retest Reliability of Speed, Change of Direction Speed, and Reactive Agility Tests

Test

Test 1

Test 2

ICC

% TE

Speed

5 m sprint (s)

1.20 ± 0.10

1.20 ± 0.10

0.84

3.2

10 m sprint (s)

1.98 ± 0.13

1.99 ± 0.11

0.87

1.9

20 m sprint (s)

3.39 ± 0.20

3.38 ± 0.20

0.96

1.3

Change of Direction Speed

505 test (s)

2.39 ± 0.17

2.37 ± 0.16

0.90

1.9

Modified 505 test (s)

2.73 ± 0.17

2.72 ± 0.17

0.92

2.5

L run (s)

5.77 ± 0.69

5.63 ± 0.38

0.95

2.8

Reactive Agility

Movement time (s)

2.50 ± 0.14

2.52 ± 0.18

0.92

2.1

Decision time (ms)

71.5 ± 47.1

71.1 ± 46.0

0.95

7.8

Response accuracy (%)

85.5 ± 16.3

85.4 ± 16.6

0.93

3.9

Table 2

Speed, Change of Direction Speed, and Reactive Agility Results for First Grade and Second Grade Rugby League Players

Test

First Grade

Second Grade

Effect Size

Speed

5 m sprint (s)

1.14 ± 0.06*

1.20 ± 0.11

0.68 (Moderate)

10 m sprint (s)

1.90 ± 0.09*

2.00 ± 0.14

0.85 (Large)

20 m sprint (s)

3.25 ± 0.16*

3.39 ± 0.21

0.75 (Large)

Change of Direction Speed

505 Test (s)

2.34 ± 0.20

2.39 ± 0.15

0.28 (Small)

Modified 505 test (s)

2.66 ± 0.14

2.71 ± 0.17

0.32 (Small)

L run (s)

6.36 ± 0.53

6.49 ± 0.40

0.28 (Small)

Reactive Agility

Movement time (s)

2.48 ± 0.17*

2.60 ± 0.16

0.73 (Moderate)

Decision time (ms)

55.3 ± 43.6

78.2 ± 40.4

0.54 (Moderate)

Response accuracy (%)

89.3 ± 13.9

84.0 ± 17.3

0.34 (Small)

Table 3

Relationship Among Speed, Change of Direction Speed, and Reactive Agility in Rugby League Players

5 m Spr

10 m Spr

20 m Spr

505 Test

Mod 505 Test

L Run

RAT MT

RAT DT

RAT RA

5 m Spr

1.00

10 m Spr

0.90+

1.00

20 m Spr

0.84+

0.96+

1.00

505 test

0.52+

0.57+

0.58+

1.00

Mod 505 test

0.61+

0.62+

0.62+

0.73+

1.00

L run

0.57+

0.64+

0.73+

0.73+

0.61+

1.00

RAT MT

0.29

0.41+

0.51+

0.40*

0.46+

0.58+

1.00

RAT DT

0.11

1.00

RAT RA

-0.03

-0.19

1.00

Table 4

Interpretation and Training Prescription for Players Based on Reactive Agility Test Results

Player Type

Decision Time (ms)

Movement Time (s)

Interpretation

Prescription

Fast Mover/Fast Thinker

58.75

2.31

Above average anticipation skills

Continue to develop change of direction speed and decision-making skills

Fast Mover/Slow Thinker

148.75

2.33

Below average anticipation skills

Needs decision-making training with reactive agility and video-based perceptual training

Slow Mover/Fast Thinker

28.75

2.85

Lacks change of direction speed

Needs training to improve physical qualities

Slow Mover/Slow Thinker

112.50

2.86

Below average anticipation skills

Needs decision-making training and speed/change of direction speed training

CONCLUSION

This study demonstrates the importance of assessing reactive agility in rugby league players, emphasizing how current tests do not effectively differentiate skill levels. The findings suggest a shift towards integrating perceptual skill evaluations, particularly reactive agility tests, into training and assessment protocols for enhanced player development. Future work should explore more game-like scenarios for evaluating reactive agility and decision-making in rugby league athletes.