Lying triceps extensions are a great mass builder, as they hit the long head of the triceps and allow you to use fairly heavy weight.
PROSECUTION
Incline lying triceps extensions increase the focus on the triceps long head more than the standard version does.
EVIDENCE
When doing triceps extensions, the farther back (toward your forehead) the elbows are the more long-head emphasis you get. This is because the long heads attach to the scapulas, so the more you bring your arms back the more the long heads are stretched and the stronger they become.
Lying triceps extensions on a flat bench are performed with the arms perpendicular to the body, and therefore there is fairly equal involvement from the long and lateral heads.
Lying triceps extensions on an incline bench are performed with the arms more overhead. This stretches and emphasizes the long head more than the flat bench version.
VERDICT: LYING TRICEPS EXTENSIONS
Because lying triceps extensions on a flat bench involve both the lateral and long heads, they are the best version for building overall triceps mass. The incline version is better for specifically bringing up the long head.
SENTENCING
Remember these points when it comes to performing lying triceps extensions.
Use a standard (flat bench) lying triceps extensions for building overall triceps mass.
Occasionally, perform incline lying triceps extensions to better hit the long head of the triceps, especially if that area is lagging.
