commonly known as FKFS
-The effect when a fat (or relatively large) kid thinks that playing the wii will make you fit.
-may cause sudden attempts (from that fat kid) of actually being athletic when clearly their are not.
'wow nathan tottaly has Fat kid 'fitness' sickness (FKFS) he tryed to flex for some girls because he stayed up all night playing wii fit
by Jon DeYonker February 27, 2009
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