If you gently squeeze the stems till they pop they will repair the damage and the stalks will become much stronger. Start closest to the main stalk on the branches and gently squeeze stems from stalk to first node on all stems. Wait a few days and repeat between the first and second nodes and so on. Constantly pinching the stalks during veg will strengthen them for flower and will improve circulation for the plant. It's kinda like the broken bone that heals stronger on the break than the rest of the bone.