Psychology 2036A/B Lecture Notes - Lecture 27: Tetany, Motor Unit, Muscle Contraction

• School: Western University
• Department: Psychology
• Course: Psychology 2036A/B
• Professor: Doug Hazelwood

Document Summary

It is the force (independent variable) that determines the velocity. If an eccentric contraction is followed by a concentric contraction there will be greater force generated during the concentric- jumping. The biceps is contracting but also lengthening while generating force (lengthening (m/s) eccentric) If you"re running down the stairs really quickly (lengthening eccentric) you can generate tremendous forces. Doesn"t matter what the muscle group is, it will act the same. Motor units are of different sizes and allow graded contraction. Sizes differ due to fibre size and number ng can. Sizes differ due to fibre size and number. Eye ball is only a little heavier than a nickel so force for movement is really minimal so motor units are very small. Large movements like jumping or weight lifting has lots of motor units (can have 1000s of fibres associated with 1 motor neuron) Allows us graded contractions depending on size of motor units depending on movement we"re trying to produce.