I once had to carry a 15 kg bumper plate around Guatemala City for four days because my cart broke the very first day at the Guatemala National Airport. Finally, one of the two bags should have everything you will need for the contest, as well as a change of clothes and incidentals like a toothbrush. The other bag will contain anything else you want to bring, but would not be devastated by the loss of. The airports still lose baggage, so keep things like cameras and passports attached to your body in some way. I have heard that they will give you some money for your loss, but this is only a rumor and nothing I, or anyone I know, has had to deal with.
Damage can also happen to the luggage itself.
Make sure your check in bag is the most durable one you are carrying. This is a general rule and may not be applicable if you strongest bag happens to be your only piece of carry-on luggage. However, when looking at bags, try to get bags that do not rely exclusively on one closure mechanism. If your bag has a zipper, then try to get one with reinforcing straps or a fold over top. Some of their lighter bags use only zippers, but they are so overbuilt that the circumstances would really have to be extreme for anything else to be necessary.