Regarding scuba, it’s worth noting that it’s incompatible with air travel to some extent. I heard a story about a guy who did a scuba dive on vacation somewhere, then got on a plane and experienced intense pain as the aircraft gained altitude because the nitrogen level in his body can’t take the pressure differences (or something like that). The pilot was forced to fly at a low altitude for the entire trip to prevent the diver from suffering. It’s probably part of scuba training but thought it should be mentioned.