Where it is and what it does
TODO(content)Origin, insertion, parts and joint actions wait for a reviewed muscle research doc (docs/research/muscles/anterior-deltoid.md) citing a verified anatomy source. The OpenStax Anatomy and Physiology entry (S025) is still marked “To verify”.
Nerve supply
TODO(content)Innervation to be added from the verified anatomy source.
How flat pressing trains it
The front deltoid works alongside the chest in every flat press, raising the upper arm forward as you press. Its measured activity was similar for barbell, dumbbell and Smith machine flat presses [1]. It takes a larger share as the bench inclines, especially above about 45° [2], which is one reason overhead and steep incline presses feel so shoulder-heavy.
Common problems
TODO(content)Brief, non-diagnostic notes on common problems wait for the muscle research doc. If you have pain in this area, see a doctor or physiotherapist.
Works alongside
- Pectoralis major (chest)
- Triceps brachii (triceps)
How sure are we
| Claim | Certainty | Basis |
|---|---|---|
| Front-deltoid activity is similar across barbell, dumbbell and Smith machine flat presses. | Moderate | [1] |
| Front-deltoid activity rises with bench incline, especially above about 45°. | Moderate | [2] |
Sources
- Saeterbakken AH, van den Tillaar R, Fimland MS. A comparison of muscle activity and 1-RM strength of three chest-press exercises with different stability requirements. J Sports Sci. 2011;29(5):533–538. Cristin recordVerified · checked 22 Oct 2026
- Rodríguez-Ridao D, Antequera-Vique JA, Martín-Fuentes I, Muyor JM. Effect of five bench inclinations on the electromyographic activity of the pectoralis major, anterior deltoid, and triceps brachii during the bench press exercise. Int J Environ Res Public Health. 2020;17(19):7339. doi:10.3390/ijerph17197339Verified · checked 22 Oct 2026