The chamber flight is an all day course at Tyndal teaching you about flying and its effects on the body. At the end of the day they put you in an altitude chamber, raise the pressure, and make you take off your mask in order to show you the effects of hypoxia. You receive a card that is valid for one year.
The water survival training is a 3-4 hour course where they spend an hour teaching you about water survival and then throw you in the water to demonstrate it. It was fairly easy. You have to light a flare, swim under a parachute, climb into different life rafts, and then release yourself from your parachute harness as you get drug behind a jet ski. The was the "hardest" part, although everyone was able to do it. The clothing that you wear is your flight suit and some sort of shoes (maybe you should wear water shoes so you don't get weighed down as much). On top of that you wear a parachute harness which weighs 5 lbs or so. Overall, there is not much added weight (the main weight is the waterlogged flight suit).
Again, as I said before, regardless of your interest in flight medicine, I would recommend this course to everyone. You get to go to easily one of the most beautiful beaches on the east coast during the weekends and fly in F15s during the weeekdays - What could be any better?