The idea of eccentric movement generally speaks to movement from or off a circular path. Picture a round shaft that rotates. Now picture a circular or disc-shaped piece rigidly attached to the end of...
A concentric movement would be flexing the elbow and curling a dumbbell towards the shoulder, an eccentric contraction would be the opposite movement ie bringing the dumbbell back down towards the...
Eccentric means, literally, "off center". The term originated with astronomy. Later, it came to be used in mechanics, to describe a wheel or gear which rotates about an axle which is not at its...