I currently train on rougly 32 square metres, in an L-shaped room with walls around the entire mat. This is not aikido, though. Aikido techniques in general take slightly more space. But we have to think all the time about where to stand when we start the technique, to use the space efficiently.
My old university dojo had 40 square metres, in a big room. The start of first term was crowded, especially as newbies don't understand in the beginning of techniques which direction they are going to throw. Later we were never more than 8 students, mostly just three of five, and one of them thought I should get more tatami. I shook my head - hey, you don't know what crowded is... I usually laid them out as 8*5 metres, but when we were many I adjusted to 10*4. 4 metres without walls works for taking throws, got to think about what you're doing though.
I used to train at a place where we had 32 square metres (350 square feet) laid out as 8*4, later improving to 40 (430). A little space between mat and walls, though, which helped. When we were more than eight people, we usually did techniques with throws as what I am taught to call kakari geiko: one person is tori, and the others stand in a line to get thrown. That I can recommend.
At crowded seminars, the teacher sometimes had us working in groups of three instead of in pairs. In a regular class where the students are fairly new, though, I think you loose a lot of tempo by this.
Last edited by Hanna B : 03-20-2004 at 02:28 AM.