Thats what i think. Not because no one else said so but they seem to work best on me. When i didnt have a bench i did them while lying on the floor.
I did have a question about them. should i lock them out, like get a full extension because i fear for my elbows. OR does it matter?
Do whatever works and doesn't hurt. To reduce the chance of elbow problems:
-Ensure the extensions are done to behind and below the head-lower the weight to below the bench, getting a full stretch. Elbow positioning isn't relevant, don't worry about keeping them in the same position. Extensions behind the head are a lot easier on the elbows that the less effective "skull crushers" which aren't worth doing.
-Warm them up by doing something like dips or pushdowns first.
-Use an E-Z/hammer bar, or 2 hands around the end of a dumbbell - easier on the joints, more intense on the triceps.
-Lie on a mild decline if possible-removes some elbow stress while hitting the tris slightly better.
-A good alternative is pulley extensions, which tend to stress the elbows less.
-Keep the reps moderate 8-12, with never more than a minute between sets to keep the tissues warmed up.
Extensions are/were Coleman's & Oliva's fave size builder. Bertil's fave was bench dips. Dillet liked the dip machine, very similar to bench dips. Extensions & bench dips/dip machine are the best combo IMO.
