When Judo was first found it was based on two main principles Seiryoku Zenyo and Jita Kyoei (with this post focusing on the former). Jigoro Kano (the founder of Judo) was a Ju-Jitsu student. He realised that Seiryoku Zenyo (often translated as “Maximum efficiency, minimum effort”) was a crucial component of techniques and worked to remove techniques that violated this idea. This meant that Seiryoku Zenyo had a huge influence on what would evolve to be Judo.
Seiryoku Zenyo is core to judo and it’s techniques. The idea that skill and technique will overcome strength is widespread in judo. Many throws take advantage of this, for example going in the same direction that an opponent is moving rather than trying to fight against an opponent. Similarly techniques such as chokes and armlocks can need surprisingly little strength to pull off.
Kano also saw Seiryoku Zenyo as a wider philosophical idea; something to be applied to life as well as on the tatami. He saw Seiryoku Zenyo as a way to self betterment (as well as for the betterment of society). In fact this is where the name Judo comes from – “The Gentle Way” versus Ju-Jitsu’s “The Gentle Art”. Kano viewed judo as a path rather than just a sport.
As a founding principle of Judo Seiryoku Zenyo is something to keep in mind both when training and in general it’s often common to push back against problems but it is often better to take the judo approach.