Step by step instructions, muscle activation and variants for the Lying triceps extension.
The lying triceps extension, also known as the skull crusher, isolates the triceps to build strength and size in the back of the upper arms. Lying on a bench keeps the upper arms fixed so the movement comes entirely from the elbows.
Common mistakes content is coming soon.
The Lying triceps extension is a foundational movement that builds strength and muscle through controlled, progressive overload. Train it 1 to 2 times per week with 3 to 5 working sets per session, gradually adding weight or reps as form holds up.