Bone mineral density may be compromised by tobacco, making bones more brittle and break-prone.

CNN: Dangers on the Home Front

Wander into any eighth-grade science fair and you're likely to see an example of this destructive process at work - place two dissimilar metals in an electrolyte solution and one of the materials will slowly steal ions from the other, causing it to oxidize, become brittle and eventually break apart.

ENGADGET: Engineering a better bicycle with DBC City Bike Design Alt

But Berdych had other ideas, targeting Federer's unusually brittle second serve to break in games two and six before serving out the 27-minute third set.

BBC: Wimbledon 2010: Roger Federer stunned by Tomas Berdych