1st Centreline
What does it mean to lose this line?
not having a hand, 3rd centreline or elbow on this line.
Why is this bad?
you are more open to being hit in fleshy parts of the body when facing a single opponent at close range.
2nd Centreline
What does it mean to lose this line?
not having an elbow as close as possible to this line when your arm(s) is on top of theirs.
Why is this bad?
your balance is compromised at close range if your elbows are high and they are pushing up into you from below.
3rd Centreline
What does it mean to lose this line?
trying to use your low wrist/hand to push up against their 3rd centreline. Also trying to use your high elbow to push down against their 3rd centreline.
Why is this bad?
they can exert more pressure on your wrist or elbow by using their 3rd centreline. It also means their hand is free to better deal with your next strike.
4th Centreline
What does it mean to lose this line?
the line is closer to you than to your opponent.
Why is this bad?
your opponent now has an angle of 135 degrees whereas your arms are collapsed. They have a much greater chance of hitting you and protecting themselves at the same time.
5th Centreline
What does it mean to lose this line?
your upper body is significantly backward or forward of this line when it is in line with the midfoot (middle of the whole foot).
Why is this bad?
your weight will now tend to fall forward or backwards meaning a greater chance of you losing your balance.