Overlap & Follow-Through...
Follow through and overlapping action help the characters look more convincing, making sure that they look like they're following the laws of physics and overall making the animation look realistic. Different parts of the body move at different rates and therefore some continue to move when the main body stops and follow the path of action in order to catch up a few frames after. Also new actions should start before the previous one finishes so that the interest wont be lost and there will be no dead pauses between actions.
"It is not necessary for an animator to take a character to one point, complete that action completely, and then turn to the following action as if he had never given it a thought until after completing the first action. When a character knows what he is going to do he doesn't have to stop before each individual action and think to do it. He has it planned in advance in his mind." Walt Disney.
"It is not necessary for an animator to take a character to one point, complete that action completely, and then turn to the following action as if he had never given it a thought until after completing the first action. When a character knows what he is going to do he doesn't have to stop before each individual action and think to do it. He has it planned in advance in his mind." Walt Disney.
Classic example:
In the video above, which is taken by Anastasia(1997) we can see follow through and overlapping action on her hair and the dress as they follow the movements of her body as she dances, adding realism to the animation and gives it a smoother feel. This attention to detail is what makes this animation look and flow realistically because if there was no follow through on her dress when she moves, it would look rigid and strange as the fabric defy's physics.
Contemporary example:
Above is a wonderful example of follow through and overlapping action as the horse's mane and tail move along, following the main body movement as the horse runs. This adds continuity to the movement and it also makes it look more real. The horse moves in a way you would expect a horse to move, and without that follow through of the mane and the tail, it wouldn't look as convincing and realistic as it does now. The video is taken from the movie called Spirit: Stallion of the Cimarron (2002).
Written by Melina Shoukri and Antonia Atsiaris