Previously I had written about training risks people will take to try and reap benfefits that are low or don't exist.  This particular incident I am about to share happened in 2005 but is buzzing currently because of legal recourse. 

"Back in 2005, 200-pound Pete Royal grabbed a pair of 75-pound dumbells and leaned back on an inflated exercise ball to start lifting. Bam! The inflatable burst from under him and Royal hit the floor sustaining serious injuries. Five surgeries later, he's now filing a lawsuit against the Jacksonville, Florida YMCA for lack of safe gym conditions, and TKO Sports Group -- manufacturer of the"anti-burst" inflatable, for mislabeling the ball."

Stability balls are great tools to help with core work and I use them frequently and safely.  I would not use the stability ball as a bench replacement especially with an almost combined weight of 400 lbs which was the problem of Pete Royal.  I'm not sure what immense gains Pete thought he would be achieving by doing dumbbell bench press on an unstable ball opposed to a commercial steel bench.  I know that the ball manufacturer claims that it was anti-burst but why would you aggresively want to put it to the test?  This mans injuries were terrible but I don't feel that sorry for him either.  This issue is beyond training risk, it just comes down to old fashioned common sense.  I will be eagerly awaiting either a settlement or jury verdict on this case. 

When exercising be smart and safe, lean on the side of caution and more importantly good reason.