in theory your body should be able to fuel its way through an intermediate distance race. fluids every 15 minutes on the bike and at every aid station on the run is the norm - water every 15 min with gatorade or whatever energy drink every hour. imo a gel is overkill on an olympic. maybe dropping one literally before the swim but even that's not really necessary if you've eaten properly during your training. 1/2 im is where fueling really begins to be make or break.