Almost every jurisdiction defines gambling the same way...if you're wagering on yourself in a competition which requires skill and not the element of chance, then it is NOT gambling.
Some have argued that poker isn't gambling because skill is involved in choosing the right cards to throw back or in bluffing, but what you're dealt and what you draw is pure chance so it will likely always be defined as gambling.
BTW - if you're betting on someone else's bowling, it is also gambling because what the bowler you're betting on does is outside of your control or skill and is therefore considered chance.
