1. Biomechanics of Skeletal Muscle and Electroymography
Readings: Hamill pp 76-81,
Electromyography
Readings: Hamill pp 81-85; Cram pp 32-37, Ch 3; DeLuca website tutorial ( ),

2. Factors Influencing Production of Muscular Tension and Applied Force
Motor unit size
Muscle Fiber Type
Selective recruitment of fiber types:
SO FOG FG
Length - tension relationship
Force-velocity relationship
Angle of pull

3. Muscle
structure

4. The motor
unit

5. Muscle Fiber Types

6. Recruitment proceeds from smallest fibers to largest
(the size principle)

7. Three-component model of muscle contraction

8. Length-tension relationship

9. Angle of pull affects turning effect, or torque

10. Length-tension, Angle of Pull Combined

11. Force- Velocity relationship

12. Electromyography The electromyogram Recording the Electromyogram
Factors affecting electromyogram
Analyzing the electromyogram
Applications of electromyography

13. The EMG
signal

15. Recording the electromyogram
Electrodes –
Size
Number
Placement
Signal conduction – wires or telemetry?
Signal conditioning
Amplification
Filtering
Analog to digital conversion
Integration
Frequency analysis

17. Filtering: Effect of different cutoff frequencies on EMG

18. Factors affecting the electromyogram

20. Analyzing the EMG signal

21. The concept of
Frequency
decomposition

22. Converting EMG from time domain to frequency domain
What is the time block,
Or window over which
Frequency analysis is
done?

23. EMG in the Frequency Domain

24. Applications of electromyography
Timing of excitation
Degree of excitation
Normalization procedures
Muscle force-emg relationship
Muscle fatigue
Clinical gait analysis
Ergonomics
Limitations of EMG

25. Timing and degree of excitation

26. EMG-force
relationship

27. Electromechanical
delay

28. Windowing is a critical step in converting EMG signal from time to frequency domain

29. The fatigue index
From EMG –
Review the
Assumptions
Inherent in this
procedure

30. Website article reading assignment
Go to website: and download tutorial article on surface electromyography detection and recording
Be prepared to answer the following questions:
What is differential amplification?
What is common mode rejection ratio?
Where should electrodes be placed?
Where should electrodes not be placed?
How large should electrodes be?
Name 3 applications of EMG signal

31. Further readings (optional) on Emg methodology
DeLuca, C. J. (1997) The use of surface
Electromyography in biomechanics.
J Appl Biomech, 19: (can be found
on delsys.com website)
Morrish, G. (1999) Surface electromyography
Methods of analysis, reliability, and main applications
Physical and Rehabilitation Medicine, 11: