Pec Dec Flyes (A bodybuilders guide)

Pec Dec Flyes

What are pec dec flyes?

If you are new to the gym scene, you may have seen the pec dec machine and wondered how to use it. Maybe you've heard the term 'pec dec flyes' and are wondering what they are and how to do them. So, what are flyes?

Pec dec flyes are a resistance exercise performed on a pec dec machine. This exercise targets the pectoral muscles in the chest by creating a resisted 'fly' movement. The exercise activates the entire pectoral muscle but will break down fibres in the inner section that pressing movements may not. 

Adding pec flyes or any other fly movement to your chest routine will lead to a fuller chest and a better defined upper body.

Which muscles are targeted by flyes?

pec dec


As with most fly exercises, the pectoral muscles in the chest are isolated. The squeezing motion of the movement means that slightly more emphasis is placed on the inner chest than would occur with pressing exercises. 

It is possible to target the upper or lower part of the chest by changing your seat height and stance. By sitting high, in a slightly reclined position, the lower part of the pectoral muscle will take the majority of the strain. 

If you wish to target the upper chest, place the seat slightly lower and lean forward. Whichever method you use, make sure that you are fully connecting with the pectoral muscle and that your shoulders are not doing the work.


How do I use a pec dec?

The pec dec is a relatively easy machine to use and the movement is easy to perform. 
  1. Select your weight and place the pin in the stack. 
  2. Adjust the seat height s that when you are seated, your elbows are resting on the pad at chest height.
  3. If the pads are set too far back, you may be able to adjust these at the top. 
  4. Take a deep breath, and upon exhale, squeeze the pads together until they meet in the middle.
  5. Hold the position for a few seconds and squeeze the chest muscles before slowly returning to the start position. Repeat this for the desired reps and sets.
Some pec decs do not have elbow pads and require you to perform the exercise with an outstretched arm. These are more commonly referred to as pec fly machines. 

They serve the same purpose and target the pectoral muscle in exactly the same way. Using a pec fly machine as opposed to a padded pec dec machine does offer an advantage. 

It makes it easier to target different parts of the pectoral muscle by changing the height of your grip and leaning forward. This is a bit trickier on a padded pec dec as the forearm pads get in the way. 

Advantages of using a pec dec machine.

The pec dec machine allows you to totally isolate the chest muscles. This means that you can focus 100% of your attention on them without having to worry about stabilising the movement. 

Flys should be part of any chest workout. Whilst presses are great for adding mass and increasing strength, the stretch and squeeze of the fly movement can target areas of the pectoral muscles that pressing movements can not. If you are a bodybuilder, it is essential to have a full, well-defined chest. 

The pec dec (or any other fly movement) should be added to the end of your chest session as it is a great finisher. The most effective method for hypertrophy is to use a light weight and use a very slow, controlled movement. 

By squeezing the pecs at the top of the exercise and focusing on a very slow negative movement, you can really tear down the fibres and get a great pump. 

Strength trainers also benefit from using the pec dec as an accessory exercise as it will strengthen the pectoral muscle and stabilise pressing movements. Whilst the hypertrophy approach may not be as beneficial for strength gains, it is easy to scale up to a heavy weight on the pec dec. 


Alternatives to pec dec flyes

Cable flys
Machine chest press
Barbell bench press
Dumbbell bench press






Previous Post Next Post

Contact Form