Construct Validity in Sports Performance Assessment

Construct Validity

• Definition: The ability of a test to accurately represent the construct or theory being measured.
• Importance: Ensures the test is relevant to the specific athlete's performance. For example, a 40-yard sprint is highly relevant for a wide receiver.
• Example: High Construct Validity is a 40-yard sprint for a wide receiver. Low construct validity is an 800-meter sprint for a wide receiver because it doesn't measure the speed relevant to their role.
• Types of Validity:
  • Face Validity: Does the test appear to measure what it's intended to measure? Important for athlete buy-in.
  • Content Validity: Assessment by experts to determine if the test covers all relevant components appropriately.
  • Criterion-Referenced Validity:
    • Concurrent Validity: Comparison with other measures taken at the same time.
    • Convergent Validity: Agreement with other valid measures.
    • Predictive Validity: Ability to predict future performance.
    • Discriminant Validity: Differentiation from unrelated constructs.

Reliability

• Definition: The consistency of a measure, essentially reproducibility.
• Key Concepts:
  • Intra-Rater Reliability: Consistency of the same rater measuring a test multiple times.
  • Inter-Rater Reliability: Consistency between different raters measuring the same test.
  • Intra: Within a single subject.
  • Inter: Between multiple subjects or raters.

Summary

• Construct validity ensures tests accurately reflect an athlete's skills relevant to their sport.
• Reliability complements validity ensuring consistent measurements. Intra- and inter-rater reliability are crucial for scoring accuracy.

Key Environmental Factors

• Temperature: High heat impairs performance.
• Humidity: Greater than 50% negatively affects endurance tests.
• Altitude: Significant for athletes transitioning from sea level.

Testing Guidelines

• Heat and Humidity: Performance can be impaired when temperatures exceed 80°F and humidity exceeds 50%. Testing can still occur, but caution is necessary.
• Altitude Acclimatization: Athletes moving to high altitudes from sea level should acclimatize for 10 days before undergoing aerobic tests. This period allows the body to adjust and achieve homeostasis.

Notes on Battery of Tests and Test Administration

• Battery of Tests: An organized sequence of tests used to assess various performance attributes.
• Protocol: Consistent order during testing is important.
• Maximizing Test Reliability:
  • Preparation: Athletes should be familiar with the tests and procedures. Practice sessions should be conducted prior to the actual tests.
  • Warm-up: Increases overall body temperature and prepares the body for activity. Specific warm-ups focus on muscles and movements used in the tests.

Consistency in Testing

• Maintain similar testing conditions (temperature, humidity, etc.) across sessions to enhance reliability.
• Follow the same procedures and order for each test to ensure accurate comparisons over time.

Statistical Evaluation of Test Data

• Descriptive Statistics:
  • Mean: Average score.
  • Median: Middle score.
  • Mode: Most frequent score.
  • Standard Deviation: Indicates spread of scores.
  • Range: Difference between highest and lowest scores.
• Z Scores: Shows how many standard deviations a score is from the mean.
• Percentile Ranks: Indicates where an individual stands relative to a normative group.

Developing an Athletic Profile

• Factors to Evaluate: Sport type, position, metabolic demands, athlete's current strength and performance metrics.
• Test Selection: Choosing valid and reliable tests.
• Post-Assessment: Repeating tests for comparison, and use results to adjust training programs.

Types of Strength Tests

• Maximum Muscular Strength (Low Speed Strength): One-rep max (1RM) for squat, bench, deadlift, isometric movements.
• Anaerobic (Maximum Muscle Power): High-speed strength tests, power cleans, hang snatches, explosive lifts.

Anaerobic Capacity

• Definition: Ability to perform high-intensity activities without oxygen.
• Typical test duration: 30-90 seconds (best results in 30-45 seconds).

Local Muscular Endurance

• Tests: Chin-ups, pull-ups, push-ups, etc.
• Measure how many repetitions can be completed to failure or in a set time.

Aerobic Capacity

• Definition: Body's ability to take in and deliver oxygen.
• Tests: 1-mile run, Yo-Yo intermittent test, laboratory VO2 max test.

Agility Tests

• Focus: Change of direction.
• Key tests: T-test, pro agility, 5-0-5 agility test.

Speed Tests

• Definition: Time taken to cover a distance (e.g., 40-yard sprint, 100-meter sprint).
• Note: 10-yard sprints are useful for assessing acceleration.

Flexibility

• Not always linked to performance but valuable for injury prevention.
• Example: High-performing athletes may have limited flexibility.

Balance and Stability

• Two philosophies:
  • Improve balance by practicing off-balance exercises (e.g., Bosu ball).
  • Build strength for better balance (e.g., single-leg squats).

Body Composition

• Measurement methods: Bioelectrical impedance, skinfold measures, etc.

Grip Types

• Supinated Grip: Palms facing up (e.g., curls).
• Pronated Grip: Palms facing down (e.g., bench press).
• Alternated Grip: One hand supinated, one pronated (personal preference).
• Other Grip: Thumb tucked under fingers.

Grip Positions

• Narrow Grip: Fingers on the initial smooth part of the bar.
• Common Grip: Slightly wider than narrow.
• Wide Grip: Used for specific lifts (power cleans, or wide-grip bench press).

Bench Press Technique

• Five Points of Contact: Head, shoulders, butt, right foot, and left foot flat on the floor.

Starting Position for Lifts

• Feet should be hip-width or shoulder-width apart.
• Maintain a neutral spine; avoid bending at the waist.

Lifting Phases

• Concentric: Muscle shortening.
• Eccentric: Muscle lengthening.

Spotting Techniques

• Spot at the wrists for dumbbells (incline, flat, or shoulder press).
• For squats, spotters should be positioned on each side.

Forward Lunge Spotting

• Spot at the hip to prevent balance issues.

Key Reminders

• Safety and proper technique are crucial.
• Practice spotting and grip variations in a controlled environment.

Stretch Reflex

• The stretch reflex is a natural reaction to a muscle being stretched, similar to a rubber band.
• Muscles store energy during a stretch, which is then released for contraction.
• Crucial for activities like sprinting, jumping, and other explosive movements.

Factors Affecting Plyometric Intensity

• Points of contact: Single-leg exercises are more intense than double-leg exercises.
• Speed: Faster movements increase intensity.
• Height: Higher jumps or drops lead to more intense exercises.
• Body Weight: Heavier individuals experience more stress on their joints.

Plyometric Training Program Variables

• Frequency: Typically 1-3 times per week.
• Recovery: 2-4 days between sessions.
• Intensity: Adjust based on exercise type and athlete's ability.
• Rest: 5-10 seconds between reps, 2-3 minutes between sets.

Plyometric Exercise Types

• Standing Jumps
• Multiple hops and jumps (e.g., depth jumps, box jumps)
• Bounding (e.g., skipping for distance)
• Box drills (e.g., box jumps, bounding onto boxes)
• Depth jumps (step off a box, then jump)

Speed-Assisted Training

• Speed-assisted training (e.g. running downhill) focuses on stride frequency
• Gravity assistance forces quicker turnover.

Monitoring Sprint Performance

• Key metrics: Ground contact time, step length, flight time, stride angle, speed, and acceleration.

Sprinting Technique Errors & Corrections

• Hip Position Too High at Start: Space feet 1.5-2 foot lengths apart, and lower into the starting position so the back leg's shin is parallel to the track surface.
• Stepping Laterally During Initial Drive: Focus on driving through the ground; avoid stepping outwards.
• Short, Tight Arm Movement: Encourage the athlete to drive elbows down and back while simulating pulling a rope.
• Excessive Tension in Neck and Upper Back: Keep the head in line with the spine and maintain a relaxed torso.

Training Considerations

• Speed resisted exercises (e.g., running with resistance bands, uphill sprints) improve stride length.
• Speed assisted exercises (e.g. , downhill running) improve stride frequency.

Training for Team Sports (e.g. Football, Basketball)

• Aerobic training is crucial, even for non-endurance athletes.
• Develop a solid aerobic base to improve VO2 max, cardiac output, and recovery.

Key Physiological Benefits of Aerobic Conditioning

• Improved VO2 max.
• Increased mitochondrial density.
• Enhanced capillary networks.
• Allows athletes to perform at a higher level and recover more quickly.

Training Strategies and Applications

• Marathon Runners: Mix of long slow distance, interval training, and fartlek training.
• Team Sports Athletes: Integrate aerobic base training in the offseason, and interval training in-season.

Key Training Modalities

• Fartlek Training: Alternating between long slow distance and tempo-paced running.
• Lactate Threshold Training: Running just below, or at the lactate threshold for improved race pace.
• Interval Training: Short, intense bursts of effort followed by rest periods.

High-Intensity Interval Training (HIIT)

• Maximal efforts with extended rest periods.
• Used for power and speed development.

Tapering

• A reduction in training intensity or volume to peak performance.

Final Takeaways

• Aerobic base is fundamental for all athletes.
• Periodization is crucial for long-term progress.
• Cross-training is a good method for maintaining fitness, preventing injury, and reducing monotony.

Max Heart Rate Method

• Calculating age-predicted max heart rate (220 - age).
• Exercise intensity is based on a percentage of this maximum heart rate.

Karvonen (Heart Rate Reserve) Method

• Heart rate reserve = age-predicted maximum heart rate (220-age) - resting heart rate
• Target heart rate = (heart rate reserve * desired intensity) + resting heart rate

Fartlek Training

• Definition: "speed play" combining continuous running with varying intensities. (e.g., sprinting a straightaway and jogging a curve on the track).
• Purpose: To improve aerobic and anaerobic capacity.
• Used to alternate between long, slow distance and faster-paced efforts.

Training Intensity Definitions

• Long Slow Distance (LSD): Building aerobic base. Used to build aerobic base (70% of VO2 Max). Focuses on increasing mileage first and then gradually increasing speed.
• Pace Tempo: Training slightly above lactate threshold. This is considered "race pace."
• Interval Training: Alternating between periods of high intensity and rest to improve VO2 max.

Interval Training (HIIT)

• Short bursts of maximal effort followed by rest periods (1:5 work-to-rest ratios are common).
• Used to develop power and strength.
• Requires sufficient rest to allow recovery.

Training for Different Sports

• Base Conditioning: Crucial even for non-endurance sports, developing VO2 max, cardiac output, and enhancing mitochondrial and capillary development.
• Cross-training: Training using different activities (cycling for runners, swimming for cyclists) to reduce injury risk and provide variety.
• Tapering: reducing training volume or intensity in preparation for competition or peak performance.
• Periodization: A structured training program that varies training intensity, volume and recovery periods over time. Linear and Block periodization are examples.
  • Linear: Training intensity gradually increases over time.
  • Block: Training is divided into blocks of specific focus (e.g., strength, power, endurance).