1. Biomechanics of Skeletal Muscle and Electrymography n Biomechanics of skeletal muscle -Readings: Hamill pp 76-81, 103-109 n Electromyography -Readings: Hamill pp 81-85; Cram pp 32-37, Ch 3; DeLuca website tutorial (see slide 31), Hildenbrand and Noble study

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

5. Muscle Fiber Types

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

10. Length-tension, Angle of Pull Combined

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

14. The signal

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

19. Factors affecting the electromyogram

21. Analyzing the EMG signal

22. Timing and degree of excitation

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

31. Website article reading assignment n Go to website: http://www.delsys.com and download tutorial article on surface electromyography detection and recordinghttp://www.delsys.com n 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

32. Further readings (optional) on Emg methodology DeLuca, C. J. (1997) The use of surface Electromyography in biomechanics. J Appl Biomech, 19:135-163. (can be found on delsys.com website) Morrish, G. (1999) Surface electromyography Methods of analysis, reliability, and main applications Physical and Rehabilitation Medicine, 11:171-205.