One group pretest post-test design

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One group pretest post-test design
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One Group Pre-Post Design Methodology

• A common example of Pre-Experimental Designs
• No control group
• No random selection of participants
• Little power to establish causation

• One Group Study Design
• Select/recruit volunteers
• Administer pre-test
• Provide Treatment
• Administer post-test

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Development of Race Profiles for the Performance
of a Simulated 2000-m Rowing Race
Kennedy Bell, 2003
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• Research Purpose
• -To create race profiles of men and women
  rowers before and after training using a
  simulated 2000-m rowing race.
• -To observe the effect of
• -Men vs. women
• -Before vs. after training

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Study Design and Methodology

• Subject characteristics
• Recruited from local rowing clubs
• Actively training for preceding 3 months
• 7 male, 11 female novice rowers
• 12 male, 8 female experienced rowers

• Informed consent Ethics approved
• by U of Alberta and Faculty of Phys.Ed.

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Study Design and Methodology

• Race Simulation Structure
• 2000 meter race in lowest time
• Performed on a Concept II Model C
• Time, distance, stroke rate, 500-m split time
  displayed for rowers
• HR, split time/500-m time stroke rate recorded
  every 200-m.

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Study Design and Methodology

• Testing Protocol (Before after training)
• 2000-m simulated race time
• Combined VT/VO2max test
• Horizon metabolic cart
• Polar Heart Rate monitor
• Multiple Repetition Maximum tests

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Study Design and Methodology

• Training Treatment Specifics
• Ten week program
• Individually prescribed and periodized
• Progressive overload
• Strength Component 2x/week
• Upper and lower body exercises
• 65-90 predicted 1-RM
• Aerobic Component 4x/week
• Three continuous and one interval workout
• Performed on Concept II Model C

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Data Analysis

• All variables collected manually from the Concept
  II display (stroke rate, time, distance, 500-m.
  split time)
• Used to calculate velocity, mean race velocity
  (MRV), deviation from MRV, and standard deviation
  of MRV every 200-m.

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Data Analysis

• Mean Race Velocity (MRV)
• Average of all race velocities taken at 200-m.
  intervals
• Deviation from MRV
• Specific race velocities taken at 200-m.
  intervals minus MRV
• Standard Deviation from MRV
• Average deviation of all participants from their
  mean race velocity at a given interval

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Data Analysis

• Race Profile Definition
• Provides a descriptive graphical illustration of
  spontaneous pacing behavior
• Is a known factor in sport performance that has
  received little attention in the sport of rowing
• Deviation from MRV plotted against MRV

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Major Findings

• Physiological Improvements

Female Pre Female Post Male Pre Male Post
VO2 Max 37 ml/kgm 45 46 56
2000m 539 sec. 496 458 426
Leg Press 148 kg. 187 297 348
Bench 18 kg. 20 78 84
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Race Profile (Male Pre-test)
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Race Profile (Male Post-test)
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Constant Pace (Fast Male Post)
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All-Out (Fast Female Post)
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Major Findings

• Differences in pacing with training
• Moved toward a constant pace model and improved
  pace
• Differences in pacing between genders
• Fastest males adhered most closely to the
  constant pace strategy
• Fastest females adhered to an all-out strategy
  not adopted by any other groups

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Discussion

• All-out pace profile (fastest women)
• Close to higher intensity sports
• Unknown if adhering to a constant pace would have
  resulted in improved performance
• Constant pace profile (fastest men)
• Close to similar well-documented sports
• Short duration cycling (4000-m.)

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Critique

• Pre-post inability to establish causation
• has no control group
• Learning effect (authors critique)
• Possible that fastest female rowers were novice
• During 2000 m test verbal encouragement used
• could affect final results
• Compared group vs. 3 fastest rowers of each sex
• should have compared novice vs. experienced
  rowers

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Critique contd

• Tested during off-season
• rowers not in physical or mental shape of race
• Transferability not good
• test is on rowing ergometer vs. boat in water
• racing strategy often dependent on situation
  relative to competitors

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Suggestions/Future Considerations

• Need to assess elite level competition to
  strongly establish nature of optimal race
  strategy etc.
• Done on water (authors suggestion)
• Compare matched groups using alternate approaches
• Compare all out strategy vs. constant for 2000 m
  race

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Other Possible Questions for Similar Research

• Specific to rowing
• what is psychologically going on during the race
• General for Pre-Post design
• add a control group
• eg. Choosing own method of rowing vs. racing
  strategy