# Why is it easier to throw someone with a judo throw?

## Main Question or Discussion Point

why is it easier to "throw" someone with a judo throw?

in judo,when we throw out opponents,the effort needed to throw them is significantly less then what one would expect.it is easier to throw a person with a judo throw than normally picking them up,moving them to the same distance,and then releasing them.why is that?

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Ryan_m_b
Staff Emeritus

It's all to do with centre of balance, essentially it's a lever action. Imagine a plank of wood balanced on a point in the middle. On one side is a 99kg weight, on the other a 100kg weight. To lift the 100kg side off of the floor one just has to apply >1kg of downward force onto the 99kg side.

Consider something simple like o goshi (hip throw); the opponent is pulled forward slightly to bring them off balance, then they are pulled onto the attackers hip at their midrift bending forward (like the plank on the point). The weight of their legs (like the 100kg weight) is pulled up by the action of their upper body falling foward (like the 99kg weight) over the attacker. Does that make sense?

i think i get it now.the torqques on both sides of the fulcrum cancel out each other.this is very much similiar to all the torques balancing each other about the centre of gravity.are the COB and the COG same thing?if they are,then can centre of gravity have interesting practical applications like this?(because most of them are just balancing things on things)

Ryan_m_b
Staff Emeritus

Not sure what you mean by COB and COG but yes this type of thing is used all the time in fields such as engineering and construction.

COB-centre of balance
COG-centre of gravity

sophiecentaur
Gold Member

I think there is more to it than simple stability, as in stopping a bus from toppling over. I reckon it's probably far more to do with the dynamics of 'control systems'. If you can sneak some spurious feedback signal into your opponent's balance system, he or she will almost throw themselves down. Let's face it, you can make someone fall over in a flight simulator when the rams are actually switched off.
Good fighters (any discipline) are working on timing and dynamics more than just brute strength. They probably haven't analysed what they're actually doing, of course - it 'just works' for them.