Buffalo Yamanoshita Aikido Suenaka-Ha
Aikido focuses on redirecting the attacker's energy in a way that off-balances them, and so is designed to require very little strength. It focuses on not resisting forces of nature, but harmonizing with them and using them to your advantage.
On a practical, physical level, one is using basic laws of physics, and "mechanical advantage" to perform a technique. On a spiritual and metaphysical level, the study of Aikido leads one to ponder how these same concepts apply mentally and psychologically.