Pec Deck – The Underdog Chest Developer

By The Atlantis Strength Editorial Team

February 13, 2023

Ask a group of men to name a muscle group that has mystique and you’re likely to have the pectoralis major come out a clear winner. This muscle, which gives the chest its classic, chiseled aesthetics, is one few men can get too much off.

Even the functional coaches and strength training experts agrees on its importance, since its horizontal adduction function is involved in every throwing, punching and anterior pushing movement.

A Deeper Look At The Anatomy

If you’re an anatomy buff, you know that the pectoralis major is a fan-shaped muscle that originated on the sternum, the sternocostal cartilage of the first six ribs and part of the proximal end of the clavicle. It then inserts on the upper portion of the arm bone, the humerus, on a landmark called the lateral lip of the bicipital groove.

As such, it is a very active muscle. It is in charge of bringing the arm to the side (adduction), internally rotating the humerus and, depending on the position of the arm, help with either flexion or extension. But it is the multi-muscle actions of doing a horizontal adduction that makes it such an important muscle. What is horizontal adduction? It is the movement of pushing something in front of you. It is involved in the bench press of course, but also in any throwing, punching and pushing motion. And as such, it played a huge part in our development.

Scientists and anatomists explain that our pectoral muscles got overdeveloped during evolution exactly because of these aforementioned throwing, punching and pushing motions. This is but one of the big difference that helped hominids dominate their niche, compared to other primates, who tend to favor shoulder musculature more than pectoral’s. Having strong pectoral development is what made our ancestors so adept at throwing. Theories on evolution state that overhead throwing was probably a key in defending a group of ancient hominids against predators. And we all know how important spear throwing was in order to bring back those brontoburgers the Flinstones loved so much.

So, this in part explains the importance pectoral development has and the love of bench pressing you see in gyms everywhere. It even gave rise to subculture phenomenon like “bench press Mondays.” Ever tried to find a free bench press station on a Monday at the gym? As rare as our hominid ancestors nowadays. Now you know why they’re all taken – we need the pec mass in order to maintain our evolutionary status.

It’s All About Pec Activation

But maybe pressing is not the best way to get the most out of our chest-training session. Other exercises do work the pectoralis major muscle quite effectively, and surprisingly the pec deck is the one that produce the best motor-unit activation and RPE readings according to one 2012 EMG study [1].

The results, published in ACE Journal, are based on surface electromyography (EMG). The study compares the EMG activity and the rate of perceived exertion (RPE) of different chest exercises: barbell bench press, peck deck machine, bent-forward cable crossovers, chest press machine, inclined dumbbell flys, dips, suspended push-ups, Swiss ball push-ups and standard push-ups.
Of those, the clear winner was… the bench press! No surprise there. But what caused a surprise was how close the second exercise was. The pec deck rated a score of 98 ± 26.4, compared to the bench press which got 100. Moreover, the peck deck also got the second highest RPE (after bench press).

It is a given though, with recent findings about EMG, that those measures are not as synonymous with hypertrophy as they once were, but they certainly are nothing to sneeze at.

Two other studies [2-3] shows that compared to the barbell bench press, the pec deck cause as much activation of the anterior portion of the deltoid, but almost no triceps contraction. Again, this is not a surprise, but those two results certainly offer hope to those who want to keep working on their chest development while suffering from an elbow injury or a torn triceps.

As with many machines, the pec deck offers the advantage of stability during execution of the movement. This is why most training experts and athletes like to use it when they want to train their pectorals to failure. Methods like rest/pause or drop sets are perfect for this piece of equipment and will provide plenty of growth stimulus to your muscles.

In Conclusion

The final word on the pec deck is how useful it can be in some sports. When you talk about functional training, the pec deck is at not even at the bottom of the list of exercise, it did not make the list, period. And yet, there is one (albeit small) study [4] that found a positive association between trunk rotation speed and golf club head speed and training your 8RM in the pec deck. So golfers now have a reason to hog the pec deck machines from the bros in the gym!

The Great Pec Fryer

If you want to try a real pectoral-building workout, here is a workout you can use. Just don’t do push-ups afterwards, as facial reconstruction is quite likely
It is based on a variation of the 8×8 methodology of iron guru Vince Gironda

Set 1 – 8 reps