A person who, usually due to the sexual stimulation he/she obtains from it, intentionally gains weight.

A backflip while moving forward, usually done off of one foot while running

A running reverse backflip that can be done off a springboard or a platform. Many people can't do them due to the mental block of going upside down, but they really aren't that hard.

Gainer is slang for the diving trick reverse. The category number is 300. For Example, a reverse flip (usually the term for gainer) is 302, and reverse double would be 304. A reverve is done when walking forward with a full approach, and not running. Many inexperienced divers run on the board, and could very easily slip. Gainer 2 and a half, 305, pike is the dive Greg Lougains hit his head on in the Olympics.

a tricking move that is a one footed back flip.

one who makes horse noises when lifting weight; also another word for taking a dump.