Best Pectoral (Chest) Muscle Exercises Backed by Science

Chest (Pectoral) Muscle Biology

The Pectoralis: Credit Bereact.com

The pectorals, the leading muscle group of the chest, are not just large muscles in the chest; they are also the powerhouse behind upper body movements. Their role in shaping the torso is just one aspect of their significance.  These muscles connect the front of the human chest to the upper arm and shoulder bones. As shown in the above figure, the pectorals comprise two main parts: the Pectoralis Major and the Pectoralis Minor.

Pectoralis Major

The pectoralis major, a large, fan-shaped muscle at the front of the chest, is not just a muscle but a marvel of human anatomy. Its role in various arm movements is a testament to the intricate design of the human body. The Pectoralis Major consists of two parts:

1. Clavicular Head: This part originates from the clavicle, commonly referred to as the collarbone. It helps flex the arm and move it inward toward the body.

2. Sternal Head: This part comes from the sternum (breastbone) and goes to the humerus (the upper arm bone). It helps bring the arms closer to the body and allows them to rotate.

Pectoralis Major Heads (Credit: teachmeanatomy.com

Pectoralis Minor

The pectoralis minor is smaller and located under the pectoralis major. It starts from the third, fourth, and fifth ribs and attaches to the coracoid process of the scapula (shoulder blade).

The pectoralis minor is a small, triangular muscle located beneath the larger pectoralis major in the chest. It originates from the third to fifth ribs and attaches to the coracoid process of the scapula (shoulder blade).

Pectoralis Minor (Credit: bodyworksprime.com)

EMG Analysis Technique

An electromyography (EMG) machine is a diagnostic tool used to evaluate the function of muscles and the nerve cells that control them. It measures the electrical activity of the muscles at rest and during contraction.

The process typically involves placing small electrodes on the skin over the studied muscle or inserting a needle electrode directly into the muscle. The EMG machine records the electrical signals generated by the muscles and displays them as waveforms on a monitor. This information is crucial for diagnosing nerve disorders, muscle diseases, and injuries. It helps healthcare professionals assess how well the muscles and nerves are functioning and can guide treatment decisions. The research below was conducted using this science-backed approach with EMG machines.

What is Maximum Voluntary Contraction

Maximum Voluntary Contraction (MVC) refers to the maximum force that a muscle or muscle group can produce voluntarily. It is typically assessed during strength testing, where the individual exerts maximum effort to contract the muscle. MVC is important in evaluating muscle function as it provides a benchmark for muscle strength and can be used to identify deficits or improvements in muscle performance resulting from training, rehabilitation, or other interventions.

In research and clinical settings, MVC is often measured using electromyography (EMG) to capture the electrical activity of the muscles during the contraction. By comparing the electrical signals and the resulting force produced, researchers can gain insights into the efficiency and health of the neuromuscular system. MVC is crucial in various applications, including sports science, rehabilitation, and muscle physiology.

What is Mean and Peak Activation

Researchers typically use mean MVC for their data. I used to think that mean activation was more critical as it measured the average activation throughout the entire repetition. However, muscles are not always active throughout an exercise's entire range of motion, especially during compound lifts.

For example, one muscle might be very active in the stretched position, while another becomes more active in the contracted position of the same exercise.

For this reason, I believe that peak MVC is a more important figure. Peak activation measures the highest point of activation during the repetition.

Still, I believe that mean activation might be more critical for bodybuilding purposes in providing constant tension, occlusion, and “the pump.” In contrast, peak activation may be more critical for sport-specific purposes, as it provides maximum tension at a particular moment for peak force production.

Study One

The American Council on Exercise (ACE) and scientists at the University of Wisconsin-LaCrosse conducted the first study I used. They used an EMG to measure the activity of the pectoralis major during nine popular chest exercises to determine which one was best.

The study involved fourteen male participants, aged 19 to 30, all with some degree of strength training experience (for more information, click here).

For weighted exercises (Bench Press, Pec Deck, Incline Dumbbell fly, and bent-forward cable crossovers), they used 80% of the participant's predetermined 1RM (one rep maximum). They were quoted as saying the following to summarise their study:

“We took nine of the most common chest exercises performed by men and women and tested which one elicited the highest level of muscle activation,” said ACE Chief Science Officer Cedric Bryant, Ph.D. “According to the EMG results, three exercises (barbell bench press, the pec deck machine and cable crossovers) were far and away the winners in terms of chest muscle activation.”

After analysing the data, the researchers decided the pectoralis major was most activated during the barbell bench press. Therefore, data-wise, all other exercises were statistically compared to that exercise and reported as a percentage of that value.

They discovered that the Pec Deck ( 98% muscle activation compared to the barbell bench press) and the bent forward cable crossover (93% muscle activation compared to the barbell bench press) elicited nearly equivalent muscle activation to the Barbell Bench Press. Likewise, ratings of perceived exertion for each of the three exercises were comparable, as seen below in the Table outlining each of the nine exercises' average EMG and RPE compared to the Barbell Bench Press.

ACE Study Nine Exercises Average EMG Result

Therefore, from this study, I would state the three optimal exercises are:

1. Barbell Bench Press - Average EMG 100

2. Pec Deck Fly Machine - Average EMG 98

3. Bent-Forward Cable Crossovers - Average EMG 93

Study Two

A second study by Boeckh-Behrens and Buskies (2000) used EMG testing to measure the degree of muscle activation in comparison to the reference exercise, the barbell Bench Press. The study identified that the Cable Crossover was the second most effective pectoral exercise compared to the barbell bench press, followed by the Butterfly Machine (Peck Dec Fly Machine) as the third most optimal chest exercise, as shown in the table below.

Interestingly, in a second area of this study by Boeckh-Behrens and Buskies (2000), the EMG was used to measure the activation of different regions of the chest muscle with the bench set up at various inclines. The results show that the Inverse (decline) bench press at -15 degrees is the most effective exercise for the pectoralis major.

Pectoral Exercise EMG Results - Boeckh-Behrens & Buskies. (2000)

Summary

From this study's results, the top three exercises for optimal Pectoral activation are:

1. Barbell Bench Press

2. Cable Cross-over

3. Dumbbell Bench Press

Study Three

This study conducted by Built With Science (click for the link) selected a sample size of three participants; the weight chosen for each exercise was 70% of each lifter's one repetition maximum (1RM). The study objective was to find the best chest exercises for:

• Upper chest

• Middle chest

• Lower chest

Here’s a list of all the chest exercises the study tested to determine the best chest exercises:

• Push-ups

• Banded push-ups

• Standing cable fly

• High to low cable fly

• Seated cable fly

• Chest dips

• Barbell bench press

• Incline barbell bench press

• Flat dumbbell press

• Incline machine press

• 15-degree incline dumbbell press

• 30-degree incline dumbbell press

• 45-degree incline dumbbell press

• Decline dumbbell press

• Pinch press

• Pec deck machine

The study placed EMG electrode sensors on the upper, middle, and lower portions of the chest to rank each exercise based on its effectiveness in each area. To ensure they could standardise the data, the study used the maximum voluntary contraction (MVC) measurement, representing the maximum activation a muscle can reach.

The study gathered this value before testing the exercises for each participant; therefore, they could accurately compare the chest exercises against their maximum values. This provides us with an accurate sense of how well a particular exercise targets our chest muscles. Getting this value wasn't easy. But we did it anyway, and we were ready to test.

Best Exercise for Each Section of the Chest

1. Upper Chest Activation: 15 Degree Incline Dumbbell Press - (60.9% of MVC)

2. Mid Chest Activation: Seated Cable Fly - (69.2% of MVC)

3. Lower Chest Activation: Seated Cable Fly - (101.2% of MVC)

Summary

From analysing all participants' results from this study, I have outlined the top five overall exercises that are most effective at targeting each of the three sections of the chest:

1. Barbell Bench Press

2. Pec Deck Fly Machine

3. Decline Dumbbell press

4. Flat Dumbbell Bench Press

5. Seated Cable Fly

Study Four

The study focused on four categories of chest exercises: barbell, dumbbell, machine, and bodyweight exercises, utilising EMG studies.

• Barbell Exercise: Flat Barbell Bench Press - EMG studies confirm that this exercise produces high activation in the pectoralis major, particularly the middle chest.

• Dumbbell Exercise: Incline Dumbbell Press - EMG studies indicate that an incline of 15 to 30 degrees optimally activates the upper chest without overactivating the shoulders. While both the barbell and dumbbell presses target the chest, the dumbbell press has a slight edge in terms of increased range of motion, allowing for better muscle engagement.

• Machine-Based Exercise: Peck Deck Machine—The pec deck machine ranks the highest in terms of EMG chest activation. Its unique advantage is its ability to isolate the chest muscles effectively by minimising the involvement of secondary muscles, such as the triceps or deltoids. This isolation is particularly effective for hypertrophy, as it maximizes chest tension throughout the movement​.

• Bodyweight Exercise: Dips - Chest dips are particularly effective at targeting the lower chest. According to EMG studies, leaning slightly forward while performing dips increases the involvement of the pectoral muscles by placing the shoulders in an extended position​.

Study Link: https://www.jefit.com/wp/exercise-tips/top-chest-exercises-backed-by-emg-studies/

Best Chest Exercises Using Study Results

Using all the study results from their Electromyography assessments of participants finding the optimal exercises based on either peak or average muscle activation during a sample of chest exercises, the below are the optimal chest pectoral exercises:

• Overall Chest Exercise: Barbell Flat Bench Press: 4 sets of 6-8 repetitions

• Mid Chest Exercise: Cable Crossover Fly's: 3 to 4 sets of 10-12 repetitions

• Upper Chest Exercise: 15-degree Incline Dumbbell Bench Press: 3-4 sets of 10-12 repetitions

• Lower Chest Exercise: Bodyweight Chest Dips: 3-4 sets of 8-10 repetitions