10 Chest Fly Variations – How to Do a Chest Fly – Illustrated Guide

illustration - How to do a flat bench dumbbell chest fly

How to do

  1. Lie down on a flat bench. Hold a dumbbell in each hand, with your palms facing each other.
  2. Lift up the dumbbells directly above your chest.
  3. With a slight bend in your elbows, lower your arms out to both sides in a wide arcing motion. You should feel the stretch in your chest.
  4. Squeeze at the peak of the movement.
  5. Finally, raise your arms back up to the starting position.
  6. Repeat for the desired number of reps.

Sets and reps

In most workout routines, 3-4 sets of 8-12 reps is a good place to start. This range is ideal for hypertrophy (muscle growth). As you become stronger, you can challenge yourself by gradually increasing the weight.

Muscles worked

The pectoral muscles, commonly known as “pecs”, are the muscles located in your chest area. They are made up of two parts:

  • Pectoralis major – This is the larger of the two muscles, and is the most visible muscle in your chest. It is fan-shaped and stretches from your collarbone and sternum to the humerus in your upper arms. It’s responsible for movements like pushing and pressing.
  • Pectoralis minor – This is the thin, flat muscle that’s located beneath your pectoralis major muscles. It stretches from your ribs to your scapula. It plays a key role in the movement and stabilization of your shoulder blades.
diagram - Showing chest muscles, with the pectoralis major and pectoralis minor labelled

The pectoralis major has two “heads”.

  • The clavicular head originates from the clavicle (collarbone) and connects to the humerus. As part of the pecs, this head helps move and medially rotate the arms, but can also independently flex the shoulder.
  • The sternal head originates from the sternum, fanning out to also connect to the humerus. This head also acts to create movement and rotation of the arms.

All chest flys and cable crossovers target your pectoral muscles. You can put more emphasis on your upper pecs (the clavicular head) by using an incline variation. Similarly, decline variations will shift emphasis to your lower pecs (sternal head).

It's a good idea to include inline, flat and decline variations of chest exercises in your chest or push day workout, whether that's the chest fly or a compound exercise like the bench press. This will ensure comprehensive and balanced development of your chest muscles.

Tips


What are chest flys?

The chest fly is a popular, upper body exercise that isolates your chest muscles to help you build bigger and strong pecs. The movement starts with your arms extended out to your sides and sees you bring them together in front of your chest. You can perform this exercise with dumbbells, a pec deck machine or with a cable machine.

Benefits of the chest fly

Isolation of your chest

When it comes to your chest, you're probably already doing one or more compound exercises in your workout routine. Bench press, push-ups and chest dips are all exercises that work your pecs, alongside other muscles including your triceps and shoulders.

It makes sense to focus your routine on compound exercises. These exercises engage multiple muscle groups at the same time. This makes your workouts more effective, both in terms of engaging more muscle and getting the most out of your time in the gym.

But, if you want to specifically work your pectorals, adding an isolation exercise to your routine can help promote targeted muscle growth and chest development. Chest flys and cable crossovers are both isolation exercises that work your pecs.

Lower injury risk

Exercises like the bench press and dumbbell press demand a significant amount of stability and control. This can make it difficult for beginners to execute with the proper form.

Particularly when lifting heavy weights, there is always a risk of injury if you perform an exercise improperly. In compound moves, you risk putting too much strain on muscle groups other than your chest.

The chest fly is a safer exercise, partly because it isolates your pecs. The wide sweeping motion of the dumbbells also makes the weights easier to manage and control.


Chest flys primarily target and strengthen your pectoral muscles. This exercise also helps increase the size of your chest, which can improve your upper body aesthetic.

The chest fly is an excellent exercise to add to your chest and triceps workout or push day workout routine. Since it's an isolation exercise, you should perform it after compound exercises like bench press to fully exhaust your muscles and promote growth.

Lying flat on the bench gives your pecs an even workout, compared against incline or decline flys which emphasize your upper or lower pecs, respectively.

photo - Man performing the pec deck chest fly
Written by

Gym Geek’s health and fitness editor.


Updated