Shizentai Yoi. Natural or Ready Stance
Yoi ( Natural Position Or Ready Position)
This is the position we go to after the karate bow (rei)
In Heiko-dachi, the feet are approximately shoulder width, outside edges of the feet are parallel. This is also a basic ready stance in Karate.
Shizen-tai or Yoi Dachi – natural position
Shizen-tai or yoi dachi translates as “natural stance” (literally, ‘natural body,’ or ‘natural body stance’). In Shizen-tai, the feet are shoulder width apart, toes pointing forward. The karateka stands up straight, facing forward. While in Shizen-tai, the karateka is usually in the yoi (ready) position, arms slightly in front of the thighs, fists clenched.
In some karate styles, shizen-tai is the same as heiko-dachi.
Here is a video showing Yoi (ready position)