1. Interpretation of Isokinetic Tests

2. Concepts Introduction Principle of isokinetics Benefits of training through isokinetic exercise Basic terminology Reading test results Curve analysis

3. Introduction Subjective/objective Criteria-based protocols Goals with reproducible data Biodex advantage !

4. Principles of isokinetics Preset fixed speed Accommodating resistance Resistance = effort Torque measured throughout ROM Muscle loaded throughout ROM 30 degree overflow –Strength –physiological

5. Functional Test Speeds Walking – 233°/s Running – 1000°/s – 1200° Ankle during running – 540°/s Train & test at fast speeds

6. Benefits of training Time rate of tension development (TRTD) –Upslope of the curve Decreased reciprocal innervation time (RIT) –Time between end of agonist and beginning of antagonist Strengthen musculotendinous junction –Reduces risk of strains

7. Basic Terminology/Interpretation Peak torque: –Absolute strength value (1 RM) Work: –Functional value of muscle performance –Torque over distance Power: –How effective the muscle can perform work over time

8. Reading test results Is the test reliable and valid? –Coefficient of variance –Large values? –Acceptable CV’s (large/small muscle groups)

9. Reading test results Percent deficit –Acceptable vs unacceptable –Negative value? –Considerations for unilateral athletes?

10. Reading test results Peak torque –Difficult to assess if used alone Peak torque/body weight –% of torque produced to body weight –Normative goals - see chart

11. Reading test results Max rep total work –Better indicator of neuromuscular function –Muscle must remain recruited during entire range –Should occur within first few reps of test Work first 1/3..work last 1/3 –Should be more work in first 1/3 –Look for consistency –Effort

12. Reading test results Work fatigue –Ratio between first 1/3 and last 1/3 –Should decrease with progress Acceleration time –Time to reach isokinetic speed Deceleration time –From isokinetic speed to zero –Eccentric control towards end of ROM

13. Curve analysis 4 regions of the curve –Time rate of torque development (TRTD)

14. Curve analysis ROM Uninvolved side ROM Involved side T FDR  Force Decay Rate

15. Curve analysis Reciprocal innervation time (V vs U)

16. Injury/condition curves

17. Chondromalacia patella Q H Q H

18. Plica syndrome

19. Patellar subluxation

20. ACL Deficiency

21. Summary Reports Absolute/relative Bilateral comparisons Unilateral comparisons SpeedRatio 60°/s60% - 69% 180°/s70% - 79% 300°/s80% - 95% 450°/s95% - 100%

22. T:BW Ratio General joint integrity MalesFemales 60°/s110%-115%60°/s85% - 95% 180°/s65% - 75%180°/s55% - 65% 300°/s45% - 55%300°/s35% - 45% 450°/s35% - 40%450°/s25% - 30%

23. Summary Correlate to clinical exam Use pre-established criteria Valid/reproducible or throw out Documents muscular performance only