2016/02/23
Introduction
Physical and cognitive demands of
prolonged batting in cricket
Match play analyses
Candice Christie (PhD)
Lab based analyses
Associate Professor and Head of Department
Authors: Christie CJ, Pote L and Goble D
Department of Human Kinetics & Ergonomics
Rhodes University
Grahamstown, South Africa
Introduction
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Information processing
Prolonged batting is a physiologically demanding task (1, 2, 3)
resulting in fatigue (4, 5, 6)
which negatively impacts sprint performance (7, 8, 9)
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Batting is also a mentally demanding task – requiring rapid decision making and
sustained attention (10)
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2016/02/23
Introduction
Introduction
Introduction
• At 120 -150 km.h-1 (bowling speed)
• Approximately 425 – 530 ms from ball release to detect and execute a shot
• 200 ms from ball bounce to interception (11)
• Time constraints on batsmen are severe
• Coupled with physical fatigue from running between the wickets
• Batsmen must be physically strong as well as mentally astute (12, 13)
• Despite this, no study to date has attempted to quantify the information processing
demands placed on batsmen
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Purpose
Methodology
Experimental design
To establish how cognition is effected following a
prolonged batting spell, likely to produce physical fatigue.
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Repeated measures (laboratory setting)
180 deliveries at 60 m.h-1/ 100km.h-1 (bowling machine)
Protocol – BATEX© (Houghton et al., 2011)
Shuttle running between popping creases (17.68 m)
• Maximal vs. self-selected stages
Table I: BATEX protocol design – Stage and run denominations.
To provide future recommendations for the assessment of
cognition in batting
Dependent Variables
Dependent Variables
Cognitive assessment
• CogState Brief Test Battery (CTB)
• Physical Performance
- Sprint Times
• Physiological Responses
- Heart Rate
- Energy Expenditure
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Exectutive function/ spacial problem solving (GMLT)
Psychomotor function/ processing speed (DETECTION)
Visual attention/ vigilance (IDENTIFICATION)
Visual learning and memory (ONE CARD LEARNING)
Attention and working memory (ONE BACK TASK)
• Pre, during and post protocol
Table II: Design Matrix
BATEX
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Physiological Responses
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Physiological Responses
Heart Rate
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Sig. increase between stages 1 6
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Stage 6 HR significantly higher
than 2 and 4
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Increasing physiological
demand suggesting physical
strain
Figure 1: Heart rate responses during high intensity stages.
Physical Performance
Cognitive Performance
Table III: Cognitive performance
Sprint Times
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Sig. increase from stages 1 -6
(Sprint times slower)
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Stage 6 significantly slower than 2
and 4 (Stage 2 fastest)
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Stage 4: threes and fours SD
compared to stage 6
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Increasing sprint times combined
with the heart rate responses
confirm physical strain (fatigue)
What’s going on in the dept
now?
Figure 2: Sprint times in response to prolonged batting.
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Cognitive Performance
Information processing
Improvements over time in:
1. Simple Reaction Time (psychomotor function and speed of processing) - SIGNIFICANT
2. Vigilance
Decrements over time in:
1. Attention and working memory
2. Visual learning and memory
3. Executive function - SIGNIFICANT
Cognitive Performance
Results Summary
ONE CARD LEARNING - Visual Learning & Memory
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Processing speed constant
- Fastest post protocol
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Accuracy in performance
significantly improves from
CTB1-CTB3
(positive effect of exercise/
learning effect??)
Physical fatigue established through
Higher HR and RPE p<0.05
Slower sprint times p<0.05
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Reduced after a prolonged
batting period
reduction in central
processing performance?
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Figure 4: Average reaction and total errors time during memory task
#
Cognitive function impaired by fatigue
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Attention and working memory (over 5-30)
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Psychomotor function (over 5-30)
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Visual attention/vigilance (over 5-30)
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Visual learning and memory (over 5-30)
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Executive function p<0.05 (overs 15-30)
significantly different from baseline (p <0.05)
significant difference between batteries (p <0.05)
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Performance Implications
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Physical/Cognitive Fatigue resulted in
• Significantly impaired exectutive function
• Decreased psychomotor function
• Impaired decision-making
• Impaired attention allocation and vigilance
Time constraints when facing a delivery increase
What’s going on in the dept
• Poor shot selection
now?
• Poor shot execution
• Loss of your wicket
Practical Significance
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A batsmen’s ability to process information is substantially
reduced when batting for 30 overs.
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Prolonged batting periods increase the chances of decision
making errors and may increase the risk of losing a wicket.
What’s going on in the dept
now?
Reduced repeat
sprint ability may increase the likelihood
of run outs and reduce the number of runs scored in a match.
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• Reduced sprinting speed
• Fewer runs/ increased potential for run outs
Decreased individual and team performance
Practical Significance
Acknowledgements
Recommendation:
Some training should combine batting periods
(preferably prolonged) and high intensity shuttle
running.
Or at least batting in a constraints-led training
environment
whengoing
fatigued
What’s
on in the dept
now?
This should accustom the batsmen to batting while
in a fatigued state.
What’s going on in the dept
now?
Allowing for them to formulate cognitive coping
strategies and hence improve performance.
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Questions?
What’s going on in the dept
now?
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