Kinesiology 2230A/B Lecture Notes - Lecture 5: Gluteal Muscles, Myocyte, Motor Unit

• School: Western University
• Department: Kinesiology
• Course: Kinesiology 2230A/B
• Professor: Glen Belfry

Document Summary

If an eccentric contraction is followed by a concentric contraction, there will be greater force generated during the concentric. March 22nd, 2017: ex: jumping quads lengthens as the knee bends then you jump; eccentric contraction following by a concentric contraction. Larger = greater the myosin/actin protein content: with a greater number of cross bridges, you can generate more force. Stimulation: force (wave summation: graph: increasing the frequency of ap using electrical stimulus and the force being generated over a short stimulus duration. In this example, the whole muscle twitch (one stimulus of contraction/relaxation cycle), took about 150msec. March 22nd, 2017: the different fiber types have much different size motor units. In a particular area in a muscle, that one motor unit has hundreds of fibers: number of fibers associated with the motor unit decreases, ex: there"s a(cid:271)out 3(cid:1012)(cid:1009) fg fi(cid:271)ers (cid:272)o(cid:373)pared to a(cid:271)out 1(cid:1010)(cid:1011) Innervating fewer and fewer fibers when going from.