Assessment and Interpretation of Muscle Strength and Power

Question 1

• Explain the purposes of conducting athlete testing.

Answer 1

• Assess athletic talent
• Identify physical abilities + areas in need of improvement
• Set goals
• Individualise a S&C program

Question 2

• Define the terms ‘validity’ and ‘reliability’ in relation to athletic testing. (GENERAL)

Answer 2

Evaluation of Test Quality
For a test to be beneficial it must have:
1. Validity: Measures what it is supposed to measure.
2. Reliability: Degree of consistency or repeatability of a test

Question 3

• Define the terms ‘validity’ and ‘reliability’ in relation to athletic testing. (VALIDITY)

Answer 3

There are several types of validity, including:
- Construct validity – Extent to which the test actually measures what it was designed to measure.
- Face validity – Appearance to the athlete + other casual observers that the test measures what it is purported to measure
- Content validity – Assessment by experts that the testing covers all relevant subtopics or component abilities in appropriate proportions
- Criterion-referenced validity – Extent to which test scores are associated with some other measure of the same ability

Question 4

• Define the terms ‘validity’ and ‘reliability’ in relation to athletic testing. (RELIABILITY)

Answer 4

Reliability
- Several ways to determine the reliability of a test; most obvious one is to administer the same test several times to the same group of athletes.
- Test-retest reliability: Difference b/w two sets of scores representing measurement error.
- Typical error of measurement: Includes equip error + biological variation of athletes
- Difference b/w two sets of scores can arise from:
- Intrasubject (within subject) variability).
- Lack of interrater (b/w raters) reliability or
agreement
- Intrarater (within raters) variability.
- Failure of the test itself to provide consistent
results

Question 5

• Understand factors to consider when selecting tests.

Answer 5

Must consider:
✓Sport specificity (e.g., metabolic energy systems, biomechanical movt patterns)
✓Athlete experience + training status
✓Age + sex
✓Environmental factors (e.g. temp, humidity, altitude)

Question 6

• Explain how to administer testing safely, correctly, and in an organised manner.

Answer 6

• For accurate test results, tests MUST be administered safely, correctly, + in an organised manner
• Health + Safety Considerations: Athletes need to be medically screened.
• Selection + training of testers: Thorough understanding of testing protocols.
• Recording spreadsheet/template/form: Needs to be developed w/ space for results + other specific details related to test.
• Test format: Planning of testing session (e.g., number of athletes assessed at once or in groups, roles/responsibilities for athletes + testers.
• Testing batteries + multiple trials: Adequate recovery b/w tests + trials.
• Sequence of tests: Minimising neg effects of prior tests

Question 7

• Be able to correctly order testing in a logical sequence.

Answer 7

• Non Fatiguing tests (e.g., height, weight, flexibility, skinfold + girth measurements, vertical jump).
• Agility tests (e.g., T-test, pro agility test).
• Max power + strength tests (e.g., 1RM power clean, 1RM squat).
• Sprint tests (e.g., 40 m sprint w/ split times at 10m + 20m)
• Local muscular endurance tests (e.g., push-up test).
• Fatiguing anaerobic capacity tests (e.g., 275m shuttle).
• Aerobic capacity tests (e.g., 2.4 km run or Yo -Yo intermittent recovery test)

Question 8

• Define maximal muscular strength and muscular power.

Answer 8

• Max muscular strength: Ability of a muscle or muscle group to exert force in one maximal effort while maintaining proper form
• Max muscular power: Ability of a muscle or muscle group to exert high force while contracting at a high velocity

Question 9

List and describe ways to assess maximal muscular strength and muscular power. (MUSCULAR STRENGTH)

Answer 9

• Quantified by the max load that can be lifted once (1-rep max [1RM]) in exercises such as the bench press + back squat.
• Non lab gold standard
• Isometrically (Muscle action when tension is produced but there is no change in the length of the muscle)
• Isokinetically Maximal tension is developed throughout the full ROM w/ speed being constant (e.g. 60, 180, 300 degrees/sec) – Lab gold standard

Question 10

1RM PROTOCOL

Answer 10

1RM Testing Protocol
- Instruct the athlete to warm-up w/ a light resistance that easily allows 5 to 10 reps
- Provide a 1-min rest period.
- Estimate a warm-up load that will allow the athlete to complete three to five reps by adding:
- 4-9 kg or 5% to 10% for upper body exercise or
- 14-18 kg or 10% to 20% for lower body exercise.
- Provide a 2-min rest period.
- Estimate a conservative, near-max load that will allow the athlete to complete two or three reps by adding:
- 4-9 kg or 5% to 10% for upper body exercise or
- 14-18 kg or 10% to 20% for lower body exercise.
- Provide a 2- to 4-min rest period.
- Make a load increase:
- 4-9 kg or 5% to 10% for upper body exercise or
- 14-18 kg or 10% to 20% for lower body exercise.
- Instruct the athlete to attempt a 1RM.
- If the athlete was successful, provide a 2- to 4-min rest period + go back to step 7. If the athlete failed, provide a 2- to 4-min rest period; then decrease the load by subtracting:
- 2-4 kg or 2.5% to 5% for upper body exercise or
- 7-9 kg or 5% to 10% for lower body exercise.
AND then go back to step 8.
- Continue increasing or decreasing the load until the athlete can complete one rep w/ proper exercise technique. Ideally, the athlete’s 1RM will be measured within three to five testing sets.
- 1RM is the heaviest load that an athlete can successfully lift

Question 11

List and describe ways to assess maximal muscular strength and muscular power. (MUSCULAR POWER + ANAEROBIC POWER)

Answer 11

Ways to Measure Anaerobic or Maximal Muscular Power
- Tests are of short duration, performed at maximal movt speeds + produced at very high power outputs.
- High-speed maximal power tests are often called anaerobic power tests.
- Anaerobic capacity tests involve maximal power output during muscular activity b/w 30 + 90 sec compared to maximal anaerobic power, which lasts no longer than a few sec

Question 12

30-second Wingate Test

Answer 12

• An alternative class of anaerobic power tests involve the use of a cycle ergometer.
• Most commonly used type is the Wingate anaerobic test.
• Resistance (proportional to body weight) is applied quickly after the athlete reaches a near-maximal pedalling rate (typically 90 to 110 rpm).
• Power calculated as work divided by time for each 5-sec time interval during the 30-sec test.

Parameters typically calculated include:
- Peak power
- Average power
- Fatigue index (i.e. ratio of max to min interval power)

Question 13

High-Speed Strength (Maximal Muscular Power)

Answer 13

• Primary energy sources for both low–speed strength (1RM test – takes ~2-4 sec) + high-speed strength (takes ~ 1 sec) is ATP-PCr.

High-speed strength tests include:
- 1RM of explosive exercises (e.g., the power clean, snatch, push jerk)
- Standing long jump
- Vertical jump
- Medicine ball chest throw