Triceps Dip

Sit on the edge of a bench or chair with your hands gripping the edge, fingers pointing forward.

Slide your butt off the bench, supporting your weight with your hands.

Bend your elbows and lower your body towards the ground, keeping your back close to the bench.

Pause for a moment at the bottom, then push yourself back up to the starting position.

Repeat for the desired number of repetitions.

Losing tension in the core or lower back partway through the movement — because Triceps Dip loads multiple joints at once, a small breakdown in bracing at the hips or spine compounds through the whole chain.

Flaring the elbows too wide or letting the hips sag/pike, which shifts load off Triceps and stresses the shoulder joint.

Rushing through reps using momentum rather than controlling both the lifting and lowering phase, which is especially important since there's no external load to force good tempo.

Attempting this exercise before building sufficient base strength and control — it has a low margin for error, so technique breakdown under fatigue is a common cause of injury.