The muscles used for bench press will change based on the angle of the bench (flat, decline, incline), grip on the bar (narrow or wide), and range of motion trained (bottom-end or top-end).
In general, the muscles used for bench press are the pecs, shoulders, and triceps. These are the muscles that contribute to pressing the bar in the vertical plane of motion. Other muscle groups such as the erector spinae, lats, and rotator cuff stabilize the bench press, including decelerating the bar (on the way down) and restrict inefficient movement patterns. Together, the prime movers and the stabilizing muscles are designed to work in collaboration to help produce maximum force and a well-coordinated movement.
However, as I said the exact muscles used changed based on various factors. So let’s dig into these concepts further and understand how you can best recruit each muscle groups when benching.
CHEST MUSCLES IN THE BENCH PRESS
The chest will largely be activated during the descent of the movement and at the bottom-end of the range of motion during the lifting phase. A wider grip (2X shoulder-width) has shown to activate the chest more than other grip styles.
If you prefer watching a brief summary of the muscles used in the bench press, here’s me explaining:
Role of The Chest
The chest is made up of the ‘upper pecs’ and ‘lower pecs’.
The upper pec includes the muscle fibers on your clavicle (collarbone), which help with shoulder flexion (like a pec fly).
The lower pec includes the muscle fibers on your sternum and ribcage, which help with horizontal flexion (bringing the arms straight overhead from the front).
Chest & Range of Motion
The pecs reach their peak activation during the bottom-end of the range of motion. However, the pecs are activated 2X as much on the descent compared with the lifting phase (Duffey 2008). This suggests that the pecs are highly activated when used to slow the bar.
If you can’t control the weight on the way down, or you fail the lift during the lower half of the lift, it might be because of weak pec muscles.
If you’re weak at the bottom of the bench press, then your chest muscle are likely the weak link.
Chest & Grip
The wider you grip the bar, the pec muscles will activate more than the shoulders and triceps (Lehman, 2005).
For example, if you measure the distance between your shoulders at 40cm, then a wide grip would be 80cm from index finger-to-index finger on the bar.
Based on research from Duffey (2008), grip width in and of itself may not be the reason why the chest is activated more in a wider grip. But rather, it’s what the wider grip causes the elbow position to do. If the elbow position is directly under the bar (not in front) then it will recruit the chest muscles more. If the elbows tuck inward then the triceps can also be activated in the wider grip.
Read more in my article on the 8 Benefits Of The Close Grip Bench Press.
Chest Muscles & Bench Angle
It’s been shown that an incline bench activates the upper pecs more than the flat and decline variations (saeterbakken et al., 2017). Specifically, it’s been shown that a 45-degree bench incline had the most activation in the pecs compared with other angles (Trebs, 2010).
When looking at the flat and decline variations, however, there isn’t any significant difference in pec activation.
Therefore, if you want more pec activation, perform an incline bench at 45-degrees, but you can pass up the decline bench because it doesn’t offer any more pec activation than flat.
My Recommendation for Activating Your Chest
To train the chest more: Train on a flat or incline bench (at 45-degrees) in a wide grip. Additionally, because the chest is activated 2X more on the descent, you could perform a slow bench press variation, bringing the bar down with a 3-5 seconds tempo. Also, since the chest is activated more in the bottom range of motion, you could perform exercises that extend the time under tension on the chest, such as long pause bench press (3-sec hold on chest) or a dead stop bench press.
Related: Check out another great exercise for the chest muscles called the Plate Pinch Press.
SHOULDER MUSCLES IN THE BENCH PRESS
The shoulders (anterior delt) will largely be activated during the mid-range of the bench press. Regardless of the grip you choose, the shoulders will activate similarly across different widths. Furthermore, the shoulders are most activated by using a high incline bench (55 degrees +) when compared with other bench angles).
Read more in my article on How Do Powerlifters Train Shoulders?
Role of The Shoulders
The shoulder is made up of the anterior deltoid (front), medial deltoid (side), and rear deltoid (back).
Only the anterior deltoid is involved in the bench press as a prime mover. It’s role is shoulder flexion (bringing the arms straight overhead from the front).
Shoulders & Range of Motion
The anterior deltoid is utilized the most in the mid-position of the bench press. Unlike the chest and triceps which have different activation levels during the descent and lift phase, the shoulders are equally active when lowering and lifting the bar, and its peak activity occurs very close to the middle of the movement, regardless of which direction the bar is moving (Duffey, 2008).
If you get stuck in the mid-range of the bench press, it might mean you have weak anterior delt muscles.
Shoulders & Grip
Various studies have shown that there is no statistical difference between shoulder activation and grip width on bench press (Saeterbakken et al, 2017, Duffey, 2008, Lehman, 2005).
You can expect that your shoulders will be activated similarly whether you choose to have a narrow, medium, or wide grip on the bar.
Shoulder Muscles & Bench Angles
The anterior delt is activated more throughout an incline bench variation. Studies have shown that the higher the incline, the more the anterior delt is activated (Trebs et al., 2010).
While I mentioned that the pec muscles are most activated at a 45-degree angle before having diminishing returns, the anterior delt becomes more activated the higher the angle (55+ degrees). Therefore, as you start to increase the bench angle higher than 45-degrees, the pecs do less of the work, and the shoulders do more. ‘
There is also no difference between shoulder activation on the decline and flat bench . So again, if you’re looking for more shoulder activation, perform a high incline or flat bench, but forget about decline.
My Recommendation for Activating Your Shoulders
To target the shoulders more: Train on a flat or incline bench (greater than 45-degrees) in a wide grip. Remember, the greater the incline, the more anterior delt activation. On a flat bench, the shoulders are most activated in the mid-range. Therefore, you can consider doing exercises that emphasize the mid-range of motion, such as a 2-stop bench press (where you stop and pause at the halfway point on the way down and up).
If you’re weak in the mid-range of the bench press, check out my article where I discuss how to fix it.
TRICEP MUSCLES IN THE BENCH PRESS
The triceps (lateral and medial head) will largely be activated during the lock-out phase of the bench press. A narrower grip (shoulder-width) has shown to activate the triceps more. Stick to the flat bench as the triceps decrease in muscle activation by up to 50% on incline bench variations.
Read more in my article on How Do Powerlifters Train Arms?
Role of The Tricep
The triceps are made up the lateral, medial, and long head.
Only the lateral and medial head of the tricep are involved in bench press as a prime mover. Their role is extending the elbow (going from bent to locked).
Tricep & Range of Motion
The triceps reach their peak muscle activation at the lock-out when the elbows extend (Duffey, 2008). I mentioned the pecs are highly activated during the descent, but this is the opposite for the triceps. They are relatively inactive as you bring the bar down to the chest, and only activate at the top of the movement on the way up.
If you fail the weight at the top end, it might be because you have weak triceps.
One of the best exercises for working the top-end range of motion is the boarded bench press.
Tricep & Grip
The triceps are activated the most in a narrow grip (Lehman, 2005). A narrow grip can be considered a shoulder-width grip.
For example, if you measure the distance between your shoulders at 40cm, then a narrow grip is when your grip is 40cm between your two index fingers on the bar.
At this grip width, the triceps have shown to be activated 2X as much when compared with a grip that is twice the distance (Lehman, 2005).
However, just as I stated above, studies have shown that the elbow position in relation to the bar is largely what determines the muscle activation (Duffey, 2008). So if the elbows are tucking in front of the bar in a narrower grip, then more triceps will be activated. But, if the elbows are stacked directly under the bar, then the pecs will have more activation (not more than in a wider grip, but some).
Tricep Muscles & Bench Angles
There is 50% less tricep activation on the incline bench when compared with the flat and decline variations (saeterbakken et al., 2017). So while you may get more chest and shoulder activation with higher inclines, tricep activation drastically reduces.
On the decline bench, the triceps are similarly activated when compared with flat bench (Trebs et al., 2010). So, if you wanted to target the triceps, you could either do flat or decline bench. But decline is generally a more awkward set-up, so I would just stick to flat benching.
My Recommendation for Activating Your Triceps
To target the triceps more: Use a narrow grip (shoulder width distance) on a flat or decline bench. Also, since the triceps are at their peak activation during the lock-out of the bench press, you could perform top-end variations such as board presses or band presses. Read my article on the 16 best tricep exercises to increase bench press strength.
You should now be convinced that in order to target each muscle group involved in the bench press there will be different angles, grips, and ranges of motion that will be most effective.
So how should you use this information?
If you’re a powerlifter, like most of our audience will be, you should prioritize the flat bench press over all variations.
My recommendation for people who want to maximize musculature is to practice on a flat bench press and strive to be in a wider grip. A good starting point for a wider grip would be a 2X shoulder width distance, and then adjust based on mobility and level of comfort.
With that said, it’s important to target each muscle group involved in the bench press through different variations.
What To Read Next?
Duffey, M. A Biomechanical Analysis of The Bench Press. A Dissertation in Kinesiology, Pennsylvania State University. 2008. https://etda.libraries.psu.edu/files/final_submissions/4136
Lehman, G. The Influencer of Grip Width and Forearm Pronation/Supination on Upper-Body MyoElectric Activity During The Flat Bench Press. Journal of Strength and Conditioning Research. 2005;19(3):587-591) [Semantic Scholar]
Trebs AA, Brandenburg JP, Pitney WA. An electromyography analysis of 3 muscles surrounding the shoulder joint during the performance of a chest press exercise at several positions. J Strength Cond Res. 2010;24:1925–1930. [PubMed]
Saeterbakken, A., Mo, D., Scott, S., Anderson, V. The Effects of Bench Press Variations in Competitive Athletes on Muscle Activity and Performance. Journal of HUman Kinetics. 2010;57:61-71. [National Library of Medicine]