This topic has always been a point of interest for me since day one of stepping in the dojo, does having a light build bring advantages or disadvantages? For me, being approximately 8 stone 6lbs (give or take) I have experienced both.
I found that that as an advantage I can bounce quite well from a heavy breakfall (I always managed to 'bounce' whenever I fell downstairs as a child) but I find many people disagree. The general consensus appears to be that if you have a fair bit of muscle hitting the floor it is less so hard on your body.
However, being a lightweight does have one major disadvantage in that you find if thrown at high speed you can 'fly'. Yes, thats right, quite literally fly off the mat. Thankfully I've never come off the mat, although there were a couple of close calls at summer school.
So, I guess being a lightweight is good, but I wouldn't mind being a stone heavier, particulary during Hikitat. (Although 'flying' is fun, you still face gravity...splat!)
