Shoulders rolling forward
Keep your chest up and shoulder blades back so the chest does the work, not the front delts.
Isolation · Machine
Pec Deck (Machine Fly)
The pec deck is a seated machine fly where you bring padded arms or handles together in front of your chest. It isolates the chest with constant tension and little shoulder stabilization demand, making it a good finisher for anyone after chest size.
- Primary
- Chest
- Starting rep range
- 10–15 reps
- Target effort
- 1 reps in reserve
- Progression
- 5 kg / one stack step
Muscles worked
The chest pulls the upper arms across the body (horizontal adduction). The front delts assist slightly, but with the elbows held in a fixed slight bend the triceps do very little.
How to set up
- Adjust the seat so the handles are at or just below shoulder height.
- Set the arms so you feel a stretch in the chest at the start without your shoulders pushing past comfort.
- Sit with your back on the pad, chest up, and shoulder blades pulled back.
- Grip the handles or place your forearms on the pads with a slight elbow bend.
How to do each rep
- Bring your arms together in a wide arc, leading with your elbows.
- Squeeze your chest when the handles meet in front of you.
- Return slowly over 2-3 seconds to a comfortable stretch.
- Keep your shoulders down and back throughout.
Common pec deck (machine fly) mistakes
Overstretching
Set the start position to a firm stretch you can control, not a range that pulls at the front of the shoulder.
Pressing instead of flying
Keep the elbow angle fixed and move in an arc rather than bending and straightening the arms.
Sets, reps, and progression
Surpass starts the pec deck (machine fly) at 10–15 reps with about 1 reps in reserve. As an isolation exercise it fits well after your main compound lifts.
Use 10-15 reps and add a plate when all sets hit the top. Because it is an isolation lift, prioritize a controlled stretch and squeeze over heavy load.
Know what to lift next time
Surpass shows what you lifted last time beside a target for this set, and adjusts it from your reps and RIR. Free on iPhone, no account needed.
Pec Deck (Machine Fly) alternatives
These train the same main muscles. Swap when the equipment is busy, something hurts, or progress has stalled for several weeks.
Programs that use it
Questions
Pec deck vs cable fly: which is better?
Both isolate the chest well. The pec deck is more stable and easier to learn; cables allow more angle options. Use whichever you can feel and progress best.
Should I do pec deck before or after bench press?
Usually after, as a finisher. Some lifters use a light set or two before pressing to warm up the chest.