The mechanical basis of movement by skeletal muscle

When a force acts on a rigid bar on one side of a fulcrum, a load can be moved on the other side of the fulcrum this 

Contraction does not necessarily imply shortening but refers only to activation of the force-generating process. In order for shortening to occur, the force generated by a muscle must be greater than the force opposing the shortening. If the two forces are equal, there will be an increase 

Functional Biochemistry in Health and Disease by Eric Newsholme and Tony Leech 2010 John Wiley Sons Ltd 

Type of exercise Description of action or contraction Change in length 

Eccentric contraction can most readily be appreciated by holding a weight in one hand close to the shoulder with the arm bent and lowering the arm from the elbow the biceps are developing tension to hold the weight but increasing in length as the arm is lowered. 

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