The seated barbell overhead triceps extension is an isolation exercise that strengthens the triceps while improving shoulder mobility and stability.
Sit on a bench, holding a loaded barbell in your lap with your hands close together, palms facing the floor. Lift the bar directly over your head with your arms fully extended and elbows locked. Lower the bar by bending the elbows without moving your upper arms.
Pause, then press the bar back to the start position by contracting your triceps.
Keep your biceps in close to your head as you lower the barbell.
Do not bend your wrists during the motion.
Keep your shoulders and elbows locked in place throughout the entire exercise.