The global popularity of Karate-do in the mid-twentieth century was anchored in the demonstration of destructive power: board breaking, brick smashing, and the instantaneous muscular clenching known as kime (極め). Shigeru Egami had mastered this heavy style in his youth. Serving as Yoshitaka Funakoshi's daily sparring partner, he threw himself into brutal makiwara conditioning and ferocious full-contact exchanges.

Yet the physical toll was devastating. In 1956 and 1957, Egami suffered severe gastric hemorrhages that required two life-threatening operations, removing most of his stomach. His weight plummeted to 37 kilograms (81 pounds). He was physically shattered, unable to lift heavy objects or clench his muscles without unbearable pain.

The Non-Contraction Breakthrough

Forced to strike without brute force, Egami asked his sturdiest disciples, led by Hiroyuki Aoki and the Rakutenkai group, to receive his blows. What they discovered transformed Shotokai:

• When a fist is clenched hard upon impact, the shock bounces off the opponent's muscular surface, causing bruising without displacing their center of mass.
• When a strike is launched with absolute physical relaxation (shizen-tai), dropping the shoulders and loosening the hand until the final fraction of an inch, energy travels like a liquid shock wave, penetrating deep into internal organs and sending the partner reeling backwards.

This research birthed what Japanese martial arts circles called the "Funakoshi-Egami Style", defined by long supple stances, soft arms, and the pursuit of spiritual unity (Heiho) rather than athletic sport competition.