Lying Dumbbell Triceps Extension

What the lying dumbbell triceps extension actually trains

A lying dumbbell triceps extension is an elbow extension exercise performed on a flat bench, holding a dumbbell in each hand above the chest and bending the elbows to lower the weights beside the ears before pressing them back up.

All three heads of the triceps brachii extend the elbow. What distinguishes this movement is that the upper arms are angled back over the head rather than at your sides, which puts the long head under stretch, because the long head crosses the shoulder as well as the elbow.

Kholinne and colleagues examined the roles of the three heads and found they are not interchangeable in elbow extension, which is why shoulder position is the variable that decides what a triceps exercise trains.

Maeo and colleagues then made the practical point directly. Elbow extension trained with the shoulder flexed, meaning the arms overhead, produced substantially greater triceps hypertrophy, especially in the long head, than the same work with the arms at the sides. A lying extension is a partial version of that. The arms are not fully overhead, but they are far closer to it than on a pushdown.

The dumbbell version has two specific advantages over a bar. Each arm works independently, so side to side differences show rather than hide, and the hands are free to sit neutral or angle slightly, which many elbows and wrists prefer to a fixed bar.

The disadvantage is getting the weights into position. Above about twenty kilos per hand, hauling them up alone becomes the hardest part of the set.

Setting up and executing

Sit on a flat bench with a dumbbell resting on each thigh. Lie back, using your knees to kick the dumbbells up as you go.

Press them to arms length above your chest with a neutral grip, palms facing each other.

Angle the upper arms slightly back towards your head so they are not perfectly vertical. This is what keeps tension on at the top and puts the long head under a little more stretch.

Set the feet flat and brace the abs.

Bend the elbows to lower the dumbbells beside your ears, keeping the upper arms still. Go until you feel a clear stretch along the back of the upper arm.

Extend the elbows to press back up, stopping just short of a hard lockout, and repeat.

The mistakes that cost you the most

Elbows flaring outwards is the fault that quietly converts this into a narrow dumbbell press. When the elbows spread, the chest and front deltoid take over. Keep them pointing at the ceiling and roughly shoulder width apart.

Upper arms swinging is the same problem in a different form. If the elbows travel forwards and backwards through the rep, you are pressing, and the stretch that made this exercise worth choosing never happens. The upper arm holds still; the forearm rotates around the elbow.

Lowering to the chest rather than beside the ears shortens the range and moves the load to the shoulders. The dumbbells travel back over your head, not down onto your ribs.

Dropping into the bottom is both unproductive and the reason this movement has a nickname involving skulls. Roig and colleagues found eccentric training produced greater strength and mass gains than concentric training, so the descent is training, not travel. Take two to three seconds over it.

And a hard lockout every rep transfers load from the triceps to the elbow joint. Stop just short and turn the rep around while the muscle is still doing the work.

Sets, reps and rest by goal

Moderate reps. Very heavy low rep work here tends to be felt in the elbows rather than the muscle.

For muscle gain, three sets of ten to fifteen with ninety seconds rest. For strength, three sets of eight to twelve with two minutes. In a fat loss phase, three sets of twelve to twenty with a minute.

Progress by reps before weight, because dumbbell increments are large relative to the load you use on an extension.

Lower over two to three seconds and pause briefly in the stretched position before reversing. Pedrosa and colleagues found partial repetitions performed at long muscle lengths produced favourable hypertrophy compared with short length partials, so if you are going to lose range as fatigue builds, lose it from the top rather than the bottom.

Pallarés and colleagues found full range work outperformed partial work overall, so aim to keep the whole range as long as your elbows are comfortable.

Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy. Six to twelve direct triceps sets a week is a reasonable target, and your pressing already contributes several.

Refalo and colleagues found sets stopped short of failure produce comparable growth to sets taken to failure, which is welcome on a movement where the failure rep involves two dumbbells above your face.

Where it fits in your split

After the pressing, as the main triceps movement of the session.

On push, pull and legs it goes on push day after the bench and overhead work. On a bro split it is the first triceps exercise on arm day. On an upper and lower split it follows the pressing in either upper session. On a full body programme it is a good choice whenever a bench is free.

It should come before pushdowns, not after. The stretched position is the part of triceps training that is easy to skip and hard to replace, so do it while you are fresh and finish with a pushdown or a kickback when you are not.

Two triceps sessions a week is plenty for most people, and much of that volume arrives free from pressing.

The choice between this and an EZ bar skull crusher is mostly practical. The bar loads more easily and progresses in small increments. The dumbbells expose imbalances and let the wrists sit where they want. If your elbows dislike a fixed bar, the dumbbells are the answer.

Variations worth knowing

The EZ bar skull crusher uses one angled bar, which is easier to load, easier to progress and easier to get into position.

The incline dumbbell extension puts the arms further overhead, which lengthens the long head more and is a straightforward upgrade if an adjustable bench is free.

The seated overhead dumbbell extension takes the arms fully overhead and produces the most stretched position of the group, at the cost of a smaller load.

The cable lying extension keeps tension on at lockout, where a dumbbell has almost none.

The cable pushdown works the arms at the sides, which trains the lateral and medial heads without the long head stretch, and is a sensible partner rather than a replacement.

And the close grip bench press is the compound version, allowing much heavier loading and building more total triceps mass per set.

What the evidence says

Kholinne and colleagues examined the distinct contributions of the long, lateral and medial heads of the triceps during elbow extension and found they behave differently, which is the anatomical case for training the arm in more than one shoulder position.

Maeo and colleagues found that elbow extension performed with the arms overhead produced substantially greater triceps growth, particularly in the long head, than the same work with the arms in a neutral position. This exercise sits between the two, closer to the overhead end than a pushdown.

Pallarés and colleagues found full range training produced better strength and hypertrophy outcomes than partial range training, supporting lowering all the way to a genuine stretch beside the ears.

Pedrosa and colleagues found partial repetitions at long muscle lengths produced favourable hypertrophy compared with short length partials, which tells you to sacrifice the top of the range rather than the bottom when fatigue arrives.

Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy, which sets the weekly volume target once pressing is accounted for.

Refalo and colleagues found comparable hypertrophy from sets stopped short of failure, which is a practical relief on a movement performed with weights above your head.

Roig and colleagues found eccentric training produced greater strength and mass gains than concentric training, which is the argument for a deliberate two to three second descent rather than a controlled fall.

Common questions

Should the dumbbells go beside my ears or to my forehead?

Beside the ears, or just past them. Taking them behind the head keeps tension on the triceps at the bottom and increases the stretch on the long head. Stopping at the forehead is fine too, but it is a slightly shorter range for no benefit.

Why do my elbows hurt?

Usually because you are locking out hard, dropping into the bottom, or using more weight than the movement can carry. Stop just short of lockout, take three seconds on the descent, and drop the load. If it persists, switch to a cable version, which is generally kinder.

Is this better than a pushdown?

For the long head, yes, because your arms are angled back and the long head crosses the shoulder. Maeo and colleagues found overhead elbow extension produced substantially more long head growth than work with the arms at the sides. A pushdown is still useful for the lateral and medial heads, so do both, in that order.

Dumbbells or an EZ bar?

The bar loads more easily and progresses in smaller steps, so it is better for adding weight over time. The dumbbells expose side to side differences and let each wrist find a comfortable angle. If your elbows dislike a fixed bar, use dumbbells.

Would an incline or overhead version be better?

Probably, if you want maximum long head stretch. Moving to an incline bench or sitting upright puts the arms further overhead, which is where the evidence points. The flat lying version is a reasonable middle ground that is easier to set up and easier to load.