Why Does Shoulder Position Change Everything for the Triceps?

The complaint "my triceps aren't growing" is very common, and the reason is usually simple: the client is only doing pushdowns and bench presses. The three heads of the triceps (long, lateral, medial) work in different proportions at different shoulder angles — and the long head, which has the greatest mass potential, is the most neglected head in most programs.

The key anatomy

The long head of the triceps is a two-joint muscle: it both extends the elbow and crosses the shoulder. When you raise your arm overhead (shoulder flexion), the long head is stretched, meaning it's loaded at a long muscle length. That's where the whole point lies.

Maeo's study: position > load

Maeo and colleagues (2023, Eur J Sport Sci) ran a controlled, 12-week comparison in 21 participants. One arm performed unilateral cable elbow extension in an overhead position, the other arm in a neutral position. The results are striking:

• Long-head volume increased 28.5% in the overhead position, versus 19.6% in the neutral position.
• Lateral and medial heads (combined): 14.6% overhead, 10.5% neutral.
• Total triceps: 19.9% overhead, 13.9% neutral.

And the most important detail: the overhead group used 34–39% lower absolute load than the neutral group. So more growth with less weight. The reason is the high mechanical tension at the long muscle length.

(Note: In the original study, the lateral and medial heads were reported combined; saying "only the lateral head grew this much" would not be methodologically correct. The real message is in the long-head and total-triceps difference.)

Don't overlap the exercises

Alves and colleagues (2018) showed that the overhead dumbbell extension stimulated the long head + lateral head more, while the lying extension stimulated the lateral head more. The practical takeaway: placing these two movements back-to-back in the same session is inefficient; one is already fatiguing the fibers the other works.

Kholinne and colleagues (2018) found that at 0–45° of shoulder elevation the long head, and above 90° the medial head, dominantly contributes to elbow extension — so the angle determines which head is the "leader."

Practical programming

In a program that takes the triceps seriously, I'd suggest two sessions a week:

• Session 1: Close-grip bench → Overhead cable extension → Pushdown
• Session 2: Dips → Skull crusher → Single-arm overhead extension

A few rules: Keep the loads on overhead extensions light (12–15 reps produce enough mechanical tension). The classic pushdown is good for the lateral/medial heads but insufficient for the long head on its own. Bench and dips don't fully cover the triceps either, because in these movements the shoulder is not in flexion and the long head works weakly.

In short: if a client's triceps are lagging and the program has no overhead movement at all, the single exercise you add will often change the picture.