Side pressure

Side pressure is the force exerted by rotating the forearm inward, using the elbow as a pivot point, forcing the forearm down in order to pin the opposing wrestler.

In a seminar for the Australian Armwrestling Federation, Devon Larratt claimed that "25-30 years ago...a lot of the great armwrestlers trained [only] side pressure" but that he wouldn't recommend anyone train it specifically today. He referred to side pressure as being "false mechanics" as the body isn't designed for massive amounts of side pressure. See video/link below for the entire side pressure portion of the seminar.