Assessment of Muscle Strength & Power

Question 1

Why do we test strength in sport?

Answer 1

• Ability to distinguish between athletes at different levels
• Indicator of ‘good’ athletic performance
• Sensitivity to training adaptations
• Availability of normative data for comparison
• Injury prevention

Question 2

How do we specify strength measures?

Answer 2

-Testing should replicate movement/activity of training
Standardise a number of factors...
-Type of movement
-Velocity of movement, joint velocity
-Posture
-Joint position
-Bilateral

Question 3

What are the advantages of Isotonic/Ansiometric strength testing?

Answer 3

-Easily performed
Able to execute similar movement to the one performed during the sporting activity
-Allows maximal and submaximal tests
-Can clearly communicate findings back to coach

Question 4

What are the disadvantages of Isotonic/Anisometric strength testing?

Answer 4

• Don’t allow for a great deal of scientific analysis
• Difficult to quantify techniques when compared to lab based tests
• Issues with accuracy and reliability
• Resistance is equal to the amount of torque developed by the weakest joint position
• Inability to test specific muscle groups

Question 5

How might an isotonic back squat be related to sprint performance?

Answer 5

Wisloff et al. 2004 correlated the 1RM half back squat with sprint performance over 30m.

Question 6

What do Lab based kinetics analysis allow?

Answer 6

• Determination of critical mechanical factors affecting performance (CM, acceleration, RFD)
• Segmental coordination analysis
• Applications: profiling, discriminative, analysis, pre-post training adaptations

Question 7

In terms of speed, what is the difference between a slow and fast SSC?

Answer 7

• Slow SSC = >250ms

- Fast SSC = <250mxs

Question 8

What are the Mechanical and Performance variables of speed and power tests?

Answer 8

• Impulse
• Take-off velocity
• Power
• Jump height
• RFD
• Speed - strength (SquatJump)
• Reactive Strength Index (DropJump)

Question 9

What determines an isotonic strength test?

Answer 9

• Fixed load
• Fixed resistance
• Fixed speed

Question 10

What are the advantages of using isometric strength tests?

Answer 10

• Muscle group isolation
• Accurate and reliable
• Quantification and detailed biomechanical analysis
• Allows collection of accurate and reliable EMG data
• Availability of normative data for comparisons

Question 11

What are the disadvantages of using isometric strength tests?

Answer 11

• Specific joint position strength, mid range often strongest
• Difficulty to elicit an MVC

Question 12

What are the pre testing considerations for isometric strength tests?

Answer 12

• Develop protocol (single, biarticular, joint angle)
• Familiarisation (2+sessions)
• Establish intra-subject stability AND reliability

Question 13

What are the testing considerations of strength testing?

Answer 13

• Calibration
• Equipment settings
• Warm-up
• Instructions
• Live Feedback

Question 14

What determines an isokinetic strength test?

Answer 14

• Variable load
• Fixed speed
• Variable resistance

Question 15

What are the advantages of isokinetic strength testing?

Answer 15

• Muscle group isolation
• Maximal resistance throughout ROM
• Quantification
• Correlation with athletic performance
• Safety
• Availability of normative data for comparisons

Question 16

What are the disadvantages of isokinetic strength testing?

Answer 16

• Not a real movement, need familiarisation runs

- Isokinetic velocities CANNOT match angular velocities attained during dynamic activities