How to do a Pec Deck
The pec deck is a machine chest-fly that squeezes the pecs through a fixed arc. Clean form keeps your back flat on the pad and drives with the elbows on the pads, not the hands. CalmArms grades the squeeze and range on each rep while counting for you.
Muscles: Chest · Anterior Deltoids
Demonstration: Pec Deck
How to do it with clean form
- 1
Sit with your back flat against the pad and forearms on the pads.
- 2
Drive your elbows together in a smooth arc until the pads nearly meet.
- 3
Squeeze the chest at the middle without collapsing your arms.
- 4
Return under control to a full stretch without letting the stack slam.
Common pec deck mistakes CalmArms catches
Pushing with the hands instead of the elbows.
Rounding off the pad or shrugging the shoulders forward.
Cutting the squeeze short in the middle.
Letting the weight yank the arms back too fast.
How CalmArms grades the pec deck
CalmArms scores range of motion and tempo on the pec deck, so a full, controlled squeeze grades higher than a short, rushed one.
Variations graded
Grade your pec deck on your next set.
Prop your phone and lift. CalmArms counts every rep and grades your form A–F, hands-free — on-device, no video uploaded.