"Bouncy" bread

Hi all,

I have been paying around with recipes recently and have been making a bread with half a cup of leftover sourdough, 3gms yeast, 500gm white flour and water. The last loaf I made I put if too much yeast by mistake. Although the b read rose well and cooked very well the bread turned out very "bouncy" when chewed, not soft but with some bounce back when you chewed it. Would this have been down to adding too much yeast?

Just interested as to why this might be the case so I can avoid it in the future.

Andrew.