Pec Deck Fly
A machine-based chest isolation exercise that moves the arms through a fixed arc, isolating the chest with less shoulder stabilization demand than a dumbbell fly.
Equipment: Gym machines (leg press, leg extension, etc.)
How to do it
- 1Sit in the machine with your back against the pad and grip the handles (or rest your forearms on the pads, depending on the machine).
- 2With a slight bend in your elbows, bring your arms together in front of your chest.
- 3Squeeze your chest at the point where the handles meet.
- 4Return under control to the starting position, allowing a comfortable stretch across the chest.
Common mistakes
- Letting the arms swing back too far, putting unnecessary stress on the front of the shoulder.
- Using momentum to slam the handles together instead of a controlled squeeze.
Sets & reps by goal
| Goal | Sets | Reps | Rest |
|---|---|---|---|
| Strength | 2-3 | 8-12 | 60-90 sec |
| Build muscle | 2-3 | 10-15 | 45-60 sec |
| General fitness | 2-3 | 12-15 | 45-60 sec |
Ranges reflect the same goal-based logic used by the workout plan tool. Actual set count in a generated plan also depends on how often this muscle group appears elsewhere in your week.
Frequently asked questions
Is the Pec Deck Fly safe for beginners?
Yes. The Pec Deck Fly is tagged as beginner-friendly in GetFitArchitect's exercise database, meaning it doesn't demand much prior strength or mobility. Start with a weight or resistance level where you can complete every rep with good form, and only add load once that feels controlled.
What muscles does the Pec Deck Fly work?
The primary mover is your chest. As a push movement, it also involves your shoulders and triceps.
What can I substitute if I don't have machines for the Pec Deck Fly?
The Barbell Bench Press targets the same primary muscle with different equipment, so it's a reasonable swap if you don't have machines available.
See the Barbell Bench PressRelated exercises
Learn more
Want a full plan built around exercises like this one? Try the workout plan tool.