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JEPonline

Cognitive Psychological Training in Combination with Explosive Power Training Can Significantly Enhance Responsiveness of Badminton Players Gunn Chansrisukot, Silpachai Suwanthada, Chaninchai Intiraporn

Faculty of Sports Science, Chulalongkorn University, Bangkok, Thailand

ABSTRACT Chansrisukot G, Suwanthada S, Intiraporn C. Cognitive Psychological Training in Combination with Explosive Power Training Can Significantly Enhance Responsiveness of Badminton Players. JEPonline 2015;18(4):17-32. This study consisted of two studies to determine the combined effects of Cognitive Psychological Training (CPT) and Explosive Power Training (EPT) on responsiveness of badminton players. Fifteen club level male badminton players (arranged in 3 groups of 5) made up the first study, which was carried out in three consecutive weeks in counter-balanced order for every level of 30%, 50%, and 70% effort using Vertimax to determine the effect on leg muscle explosive power during the lateral lunge. The findings indicate that peak power at 70% effort was statistically higher (P<0.05) than that at 50% and 30% effort. The second study determined the combined effect of CPT and EPT on Reaction Time (RT), Movement Time (MT), and responsiveness in terms of Response Time (RP) in badminton players. Forty club level male badminton players were randomly placed into 4 groups of 10, and trained 3 d·wk-1 for 8 wks. The control group engaged in Normal Badminton Training (NBT) while the 1st group engaged in CPT and NBT, the 2nd group engaged in EPT and NBT, and the 3rd group engaged in combined CPT, EPT, and NBT. The findings indicate that the decreases in RP in the 2nd and 3rd group were not different, but was statistically (P<0.05) better than the 1st and control group. It was concluded that supplementary training with EPT and combined CPT and EPT for 8 wks significantly reduced RP in club level male badminton players, and that supplementary training with combined CPT and EPT can reduce both RT and MT.

Journal of Exercise Physiologyonline

August 2015 Volume 18 Number 4

Editor-in-Chief Tommy Boone, PhD, MBA Review Board Todd Astorino, PhD Julien Baker, PhD Steve Brock, PhD Lance Dalleck, PhD Eric Goulet, PhD Robert Gotshall, PhD Alexander Hutchison, PhD M. Knight-Maloney, PhD Len Kravitz, PhD James Laskin, PhD Yit Aun Lim, PhD Lonnie Lowery, PhD Derek Marks, PhD Cristine Mermier, PhD Robert Robergs, PhD Chantal Vella, PhD Dale Wagner, PhD Frank Wyatt, PhD Ben Zhou, PhD Official Research Journal of the American Society of

Exercise Physiologists

ISSN 1097-9751

Official Research Journal of the American Society of Exercise Physiologists

ISSN 1097-9751

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Key Words: Cognitive Psychological Training, Explosive Power Training, Responsiveness, Response Time, Reaction Time, Movement Time INTRODUCTION Badminton is rated as an ultra-fast game [36], which is why faster players have an advantage over slower competitors [6]. Yet, it is challenging for coaches to train their players for faster movement [8]. Raw speed alone is not the answer to winning a badminton game [28]. Moving right, moving fast with laser-point accuracy [18], and executing proper technique and tactic are recognized as being important to success. Also, Cognitive Psychology, which conceptualizes the human as an information processor [20,26,27] in combination with muscle explosive power can improve the players’ responsiveness Although badminton players have a lot of information to process, they have little time from receiving information to making the right decision and executing it. Mastering motor learning and control [1,12,13,19,23,30,31] has been the ultimate goal in developing and acquisition of technical and tactical skills. Therefore, improving responsiveness in terms of Response Time, Reaction Time and Movement Time have to be improved as well (Figure 1) [20].

Units of time

Foreperiod Reaction time Movement time

Performance time

Anticipation timePlan response

Initiate response Perform and modify (if needed) response

Start End

WamingStimulus

Begin movement

Finish movement

Figure 1. Diagram Depicting Relationship among Reaction Time, Movement Time, Response Time, Foreperiod and Related Quantities.

To improve Movement Time, Explosive Power Training would appear to be the answer [29,32,33]. Typical body building muscle strength training would not be appropriate for badminton players since the neuromuscular system is not trained for repeated rapid execution [2,11,15,17,21-25,34-38]. The primary purpose of this study was to evaluate the isolated and combined effect of Cognitive Psychological Training with Explosive Power Training. Also, specific training drills were proposed to accomplish the objective of developing a training system to significantly enhance responsiveness of

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badminton players. It is anticipated that the drills will become an integral part in periodization training plan [7] for badminton players. METHODS Subjects The subjects were male badminton players 14 to 18 yrs of age. They were training in preparation for national and international competitions at badminton clubs in Bangkok. All subjects passed the inclusion criteria. In the first study, 15 subjects from Thonburi Badminton Club were sampled to determine proper loading in terms of percentage of maximum effort with Vertimax for Explosive Power Training (EPT) that was used in second study. In the second study, 40 subjects from T. Thailand Badminton Club were sampled and randomly assigned to 4 groups of 10 to determine the isolated and combined effects of Cognitive Psychological Training (CPT) and EPT compared to the control group with only typical Normal Badminton Training (NBT). Procedures The purpose of the first study was to determine optimal loading for EPT using the Vertimax V6 Pro with a high speed motion capture system. As power is calculated by multiplying force times speed of movement, force was determined by the tension of the selected cable in Vertimax and speed was measured from the motion capture system. The Elasticity Constant in Newtons per meter of three available cable types in Vertimax were assessed and tabulated in Table 1 to determine the pulling force for the power calculation. Fifteen subjects were purposively sampled and grouped into 3 groups of 5 to undergo assessment for peak explosive power at their 30%, 50%, and 70% effort for both forehand (Figure 2) and backhand lateral lunge movement (Figure 3) for 3 consecutive weeks in counter-balanced order (Table 2) for every level of effort. The results were recorded cumulatively for assessment of optimal level of effort for subsequent EPT in the second study. Table 1. Elasticity Constant in Newtons per Meter of Each Cable Size at Various Settings.

Setting Number Small Cable Medium Cable Big Cable

0

6.34

15.19

23.82 1 7.46 16.78 24.26 2 7.62 20.15 25.25 3 8.95 25.42 36.48 4 10.15 27.34 40.25 5 13.51 28.36 -

Table 2. A Counter-Balanced Order Design was used in the First Study. 30% Effort 50% Effort 70% Effort

1st Week

1st Group

2nd Group

3rd Group 2nd Week 2nd Group 3rd Group 1st Group 3rd Week 3rd Group 1st Group 2nd Group

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(A)

(B)

(C)

Figure 2. Peak Power Assessment of Forehand Lateral Lunge Movement. Using Vertimax V6 Pro at Various Load Settings and a High Speed Motion Capture System to Assess Force and Speed of Forehand Lateral Lunge Movement from Starting Line (A) over Lateral Lunge Distance (B) to Finishing Line (C) with Badminton Racket Hitting the Hanging Shuttlecock Target.

(A)

(B)

(C)

Figure 3. Peak Power Assessment of Backhand Lateral Lunge Movement. Using Vertimax V6 Pro at Various Load Settings and a High Speed Motion Capture System to Assess Force and Speed of Backhand Lateral Lunge Movement from Starting Line (A) over Lateral Lunge Distance (B) to Finishing Line (C) with Badminton Racket Hitting the Hanging Shuttlecock Target. The purpose of the second study was to isolate and combine effect of CPT and EPT compared to typical NBT. Forty subjects were randomly grouped into 4 groups of 10 to be trained 3 d·wk-1 for 8 wks. The control group engaged in Normal Badminton Training (NBT) while the 1st group engaged in CPT and NBT, the 2nd group engaged in EPT and NBT, and the 3rd group engaged in combined CPT, EPT, and NBT. Besides NBT, the 1st Group and the 3rd Group engaged in CPT for 30 min·d-1 3 d·wk-1 for 8 wks with drills shown in Figure 4 to 8.

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(A)

(B)

(C)

Figure 4. Cognitive Psychological Training #1 – Drop and Catch Drill. (A) Looking at the Reaction Ball While Holding It. (B) Releasing the Ball. (C) Anticipating Ball Bouncing Trajectory and Trying to Catch the Ball As Fast As Possible during First Bounce.

(A)

(B)

(C)

Figure 5. Cognitive Psychological Training #2 – Wall Toss Drill. (A) Squatting Facing a Wall about Twice Lunge Distance While Holding the Reaction Ball. (B) Throwing the Ball against the Wall. (C) Anticipating Ball Bouncing Trajectory and Trying to Catch the Ball As Fast As Possible during First Bounce.

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(A)

(B)

(C)

Figure 6. Cognitive Psychological Training #3 – Wall Roll Drill. (A) Squatting Facing a Wall at about Twice Lunge Distance While Holding the Reaction Ball. (B) Throwing the Ball against the Wall at Low Level. (C) Anticipating the Ball Bouncing Trajectory and Lateral Lunging towards the Ball the Moment It Touches the Ground to Catch It As Fast As Possible during First Bounce.

(A)

(B)

(C)

Figure 7. Cognitive Psychological Training #4 – Left or Right Drill. (A) Standing at a Lunge Distance in front of the Trainer with a Reaction Ball in Each Hand Wide Spreading Apart. (B) Anticipating Which Side the Ball Will Be Randomly Released and Its Trajectory. (C) Lunging towards the Dropping Ball to Catch It As Fast As Possible Before Touching the Ground.

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(A)

(B)

(C)

Figure 8. Cognitive Psychological Training #5 – Ball Drop Drill. (A) Standing at about twice Lunge Distance in front of the Trainer with a Reaction Ball in one hand. (B) Anticipating the Ball Trajectory as It Bounces from Random Drop Height. (C) Lunging towards the Bouncing Ball to Catch It As Fast As Possible during First Bounce. Besides NBT, the 2nd Group engaged in drills shown in Figure 9 to 10 for 30 min·d-1, 3 d·wk-1 for 8 wks. The 3rd Group engaged in combined CPT and EPT for a total of 60 min·d-1, 3 d·wk-1 for 8 wks with drills shown in Figure 4 to 10.

(A)

(B)

Figure 9. Explosive Power Training #1 – Forehand Lateral Lunge Drill. (A) Standing on Feet about Shoulder Width Apart. (B) Lateral Lunging towards Given Line with Right Leg as Farthest Position for Forehand Reception as Fast and Forcefully as Possible.

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(A)

(B)

Figure 10. Explosive Power Training #2 – Backhand Lateral Lunge Drill. (A) Standing on Feet about Shoulder Width Apart. (B) Lateral Lunging towards Given Line with Right Leg as Farthest Position for Backhand Reception as Fast and Forcefully as Possible. By the end of the 8th-wk, all subjects were scheduled for final assessment of their Reaction Time (RT), Movement Time (MT), and Response Time (RP) using the equipment shown in Figure 11. They were tested as shown in Figures 12 and 13 to compare with their pre-test results.

Figure 11. Equipment Setup for Assessing Reaction Time, Movement Time and Response Time. A 200-Hz High Speed Motion Capture and Analysis System with a Force Platform, Two Lamps as Stimulants and Two Shuttlecocks Hung at 45 cm Height and 2.53 m Either Side Away from the Center of Force Platform.

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Figure 12. Subject under Test for Assessing Reaction Time, Movement Time, and Response Time.

(A)

(B)

(C)

Figure 13. Test for Assessing Reaction Time, Movement Time and Response Time. (A) Standing Alert in Anticipation of Light Signal from Either One of the Two Lamps. (B) Lunging in the Direction of the Lit Lamp. (C) Hitting the Hanging Shuttlecock in That Direction with the Racket as Marker for End Point of Movement. Statistical Analysis One way analysis of variance and paired sample t-test methods were used to analyze difference of means among groups of comparison with repeated measures and post hoc analysis using Bonferroni Method for statistical analyses of both studies. Analyses were performed using the statistical package SPSS 17.0. RESULTS In the first study, peak power, peak force, and maximum speed comparisons are presented in Table 3 and 4 for forehand and backhand lateral lunge movement at 30%, 50%, and 70% effort (with .05 level of significance).

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It was found that peak power and peak force at 70% effort were significantly higher than at 50% effort, and both at 50% effort were also significantly higher than peak power and peak force at 30% effort. The maximum speed at 30% effort was significantly higher than that at 50% effort, and that maximum speed at 50% effort was significantly higher than that at 70% effort. Table 3. Comparison of Peak Power, Peak Force and Maximum Speed at Various Load Settings in Terms of Percentage of Effort during Forehand Movement.

Cable Load Setting 30% Effort 50% Effort 70% Effort F Sig

Dependent Variables ± SD ± SD ± SD Peak Power (Watt) 41.32 ± 9.55 56.32 ± 11.97 74.59 ± 15.67 26.02 0.00* Peak Force (Newton) 23.34 ± 5.40 34.74 ± 6.65 50.80 ± 10.37 47.35 0.00* Maximum Speed (m·s-1) 1.77 ± 0.08 1.62 ± 0.10 1.47 ± 0.08 48.06 0.00*

*P<0.05 Table 4. Comparison of Peak Power, Peak Force and Maximum Speed at Various Load Settings in Terms of Percentage of Effort during Backhand Movement.

CABLE LOAD SETTING 30% Effort 50% Effort 70% Effort F Sig

Dependent Variables ± SD ± SD ± SD Peak Power (Watt) 48.83 ± 11.81 65.15 ± 14.51 83.98 ± 17.53 21.18 0.00* Peak Force (Newton) 24.93 ± 5.94 36.18 ± 7.53 52.18 ± 10.19 43.09 0.00* Maximum Speed (m·s-1) 1.99 ± 0.08 1.80 ± 0.10 1.61 ± 0.11 56.57 0.00*

*P<0.05 In the second study, Reaction Time, Movement Time, and Response Time pre-post comparisons for forehand and backhand lateral lunge movement among the 4 groups are presented in Tables 5 to 8 and Figure 14 (with .05 level of significance). Table 5. Comparison of Forehand Movement Reaction Time, Movement Time, and Response Time among Groups before Training.

BEFORE TRAINING – FOREHAND MOVEMENT Control

Group 1st

Group 2nd

Group 3rd

Group F Sig

Dependent Variables ± SD ± SD ± SD ± SD Reaction Time (s) 0.249 ± 0.05 0.237 ± 0.04 0.229 ± 0.06 0.223 ± 0.06 0.44 0.72 Movement Time (s) 0.910 ± 0.05 0.911 ± 0.05 0.922 ± 0.03 0.926 ± 0.04 0.34 0.79 Response Time (s) 1.159 ± 0.06 1.148 ± 0.07 1.151 ± 0.05 1.149 ± 0.05 0.07 0.97

Table 6. Comparison of Backhand Movement Reaction Time, Movement Time, and Response Time among Groups before Training.

BEFORE TRAINING – BACKHAND MOVEMENT Control

Group 1st

Group 2nd

Group 3rd

Group F Sig

Dependent Variables ± SD ± SD ± SD ± SD Reaction Time (s) 0.220 ± 0.05 0.207 ± 0.05 0.213 ± 0.05 0.219 ± 0.06 0.12 0.94 Movement Time (s) 0.936 ± 0.06 0.927 ± 0.04 0.912 ± 0.08 0.927 ± 0.05 0.25 0.85 Response Time (s) 1.146 ± 0.06 1.134 ± 0.05 1.125 ± 0.05 1.145 ± 0.05 0.34 0.79

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Table 7. Comparison of Forehand Movement Reaction Time, Movement Time and Response Time among Groups after 8-Week Training.

AFTER 8-WEEK TRAINING – FOREHAND MOVEMENT Control

Group 1st

Group 2nd

Group 3rd

Group F Sig

Dependent Variables ± SD ± SD ± SD ± SD Reaction Time (s) 0.226 ± 0.02 0.195 ± 0.01 0.246 ± 0.04 0.166 ± 0.02 16.83 0.00* Movement Time (s) 0.927 ± 0.05 0.926 ± 0.03 0.814 ± 0.02 0.897 ± 0.01 28.77 0.00* Response Time (s) 1.152 ± 0.05 1.121 ± 0.04 1.093 ± 0.05 1.063 ± 0.01 9.48 0.00*

*P<0.05 Table 8. Comparison of Backhand Movement Reaction Time, Movement Time and Response Time among Groups after 8-Week Training.

AFTER 8-WEEK TRAINING – BACKHAND MOVEMENT Control

Group 1st

Group 2nd

Group 3rd

Group F Sig

Dependent Variables ± SD ± SD ± SD ± SD Reaction Time (s) 0.228 ± 0.03 0.167 ± 0.04 0.260 ± 0.04 0.180 ± 0.01 15.10 0.00* Movement Time (s) 0.924 ± 0.05 0.930 ± 0.03 0.829 ± 0.05 0.858 ± 0.04 14.49 0.00* Response Time (s) 1.152 ± 0.06 1.107 ± 0.05 1.088 ± 0.03 1.037 ± 0.04 10.86 0.00*

*P<0.05

0.91 0.927

0.4

0.6

0.8

1

1.2

1.4

sec.

Forehand Control Group

0.936 0.924

0.4

0.6

0.8

1

1.2

1.4

SEC.

Backhand Control Group

0.911 0.926

0.4

0.6

0.8

1

1.2

1.4

sec.

Forehand 1st Group

0.927 0.93

0.4

0.6

0.8

1

1.2

1.4

sec.

Backhand 1st Group

28

0.922

0.814

0.4

0.6

0.8

1

1.2

1.4

sec.

Forehand 2nd Group

0.9120.829

0.4

0.6

0.8

1

1.2

1.4

sec.

Backhand 2nd Group

0.926 0.897

0 4

0.6

0.8

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1.2

1.4

sec.

Forehand 3rd Group

0.9270.858

0.6

0.8

1

1.2

1.4

sec.

Backhand 3rd Group

Figure 14. Forehand and Backhand Movement Comparison Graphs among Four Groups before and after 8-Week Training After 8 weeks of training, the 1st Group with CPT alone, and the 3rd Group with combined CPT and EPT improved Reaction Time (RT). While not being statistically different from each other, both groups were better than the 2nd Group with EPT alone and the Control Group. The 2nd Group with EPT alone and the 3rd Group with combined CPT and EPT improved Movement Time (MT). Both were not statistically different from each other, but were better than the 1st Group with CPT alone and the Control Group. The 2nd Group with EPT alone and 3rd Group with combined CPT and EPT improved their Response Time (RP). Both were not statistically different from each other, but were better than the 1st Group with CPT alone and the Control Group. From comparison within group, it was found that 1st Group with CPT alone significantly improved RT while MT and RP were not statistically improved. Group 2 with EPT alone significantly improved MT and RP, but there was no change in RT. The 3rd Group with combined CPT and EPT significantly improved RT, MT, and RP while the Control Group (with the typical NBT) remained unchanged in RT, MT or RP. DISCUSSION The overall objective of this study was to develop a training system to improve responsiveness to cope with ultra-fast badminton game demand by integrating Cognitive Psychological Training with Explosive Power Training. The Vertimax was used to improve explosive power, that is, to move faster

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resulting in less Movement Time (MT). The question was then at what percentage of effort would be optimal for badminton training to balance between increasing force with reducing speed [3-5,9-11,14, 16,32]. From statistical analysis results of the first study, peak force and peak power at 70% effort were higher than those at 50% and 30% effort, while maximum speed at 30% effort was higher than that at 50% and 70% effort. Although the purpose of training was to increase speed, the higher maximum speed occurred at the lower force and power. Thus, we decided to go for highest peak power at 70% effort for training in the second study to improve explosive power. Interestingly, the findings in the present study demonstrate that the 2nd Group with EPT alone and the 3rd Group with combined CPT and EPT significantly improved MT. From the Cognitive Psychological Training [20] perspective, which emphasizes how players process incoming information, make decisions, and execute movements at precisely the optimal speed for a given split-second situation, the CPT drills used in the present study significantly improved the subjects’ Reaction Time (RT). This finding was evident in the 1st Group with CPT alone and the 3rd Group with combined CPT and EPT. As to the isolated study of the effect of EPT alone, the 2nd Group (EPI) significantly improved MT without an improvement in RT while the 1st Group (CPT) significantly improved RT without an improvement in MT. With regards to the effect of CPT in combination with EPT, the 3rd Group significantly improved both RT and MT with a resulting RP improvement. Cognitive Psychological Training in combination with Explosive Power Training significantly enhances responsiveness in badminton players.

Limitations of this Study The subjects in both phases of this study were limited to badminton club level male badminton players in Bangkok in preparation for national and international competition. Their age and body weight ranged from 14 to 18 yrs and 57 to 78 kg, respectively. The subjects’ height and leg length ranged from 166 to 187 cm and 94 to 109 cm, respectively. Further study should compare differences in female players in terms of cognitive psychological factors and explosive power development. Furthermore, incorporating Cognitive Psychological Training and Explosive Power Training to novice badminton players should enhance their badminton specific responsiveness. Also, it is reasonable to expect that these supplementary trainings should be applied to adult national players to provide them with an advantage over competitors who have not been exposed to this type of typing. Also, it is important to point out that the findings in the present study are limited to only a few badminton specific movements. Additional research and analysis should consider covering technical and tactical badminton drills with combined cognitive psychological training and explosive power training. Furthermore since reaction balls were used in Cognitive Psychological Training, addition analysis should consider using the shuttlecock to set up drills to simulate badminton scenarios in diverse tactical situations. Likewise a table tennis ball can be used on rough uneven hard surface to increase level of difficulty in anticipation of a bouncing trajectory and faster flight speed for faster and more accurate information processing, complex decision making, and the swift to powerful laser-point accurate movement.

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CONCLUSIONS The findings indicate that supplementing Cognitive Psychological Training in combination with Explosive Power Training used in this study significantly enhances responsiveness in the Response Time of club level badminton players and reduces both Reaction Time and Movement Time. Cognitive Psychological Training plays a major role in improving information processing effectiveness and efficiency in reducing Reaction Time and enhancing neuromuscular coordination and communication, while Explosive Power Training boosts speed of movement reducing the players’ Movement Time. This synergy has brought about combined effects in reducing Response Time to enhance responsiveness of badminton players. ACKNOWLEDGMENTS: The authors are grateful to the Faculty of Sports Science, Chulalongkorn University, for permission to publish this paper. The authors are also grateful for the research grant from Ratchadaphiseksomphot Endowment Fund in commemoration of the 90th Anniversary of Chulalongkorn University. The authors would like to give special thanks to participating Thonburi Badminton Club and T. Thailand Badminton Club badminton players for their cordial collaboration in this study. Also, the authors would like to express their deep appreciation to Dr. Boonsakdi Lorpipatana for his resourcefulness, guidance, and assistance in preparation of this manuscript. Address for correspondence: Dr. Chaninchai Intiraporn, Faculty of Sports Science, Chulalongkorn University, Rama 1 Rd, Pathumwan, Bangkok 10330, Thailand. Telephone: +66 81 365 7351, Fax +66 2 218 1091. Email: c.intiraporn@yahoo.com

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