For chest growth
For chest growth, cable fly and pec deck score the same on every criterion, so use whichever is free, or both.
Both are good choices that train the chest the same way, so they swap freely. Rotating between them every few weeks is an easy way to vary your training.
The research score comes from these, scored by hand from the studies. Lifter scores appear once an exercise has 10 ratings. How scores work
Cable Fly. Constant tension that stays high in the stretch, and almost nothing else limits the set.
Pec Deck. Isolates the chest with a fixed path, so every rep is the same quality.
For chest growth, cable fly and pec deck score the same on every criterion, so use whichever is free, or both. Both are good choices that train the chest the same way, so they swap freely. Rotating between them every few weeks is an easy way to vary your training.
About the same: both are easy to learn.
Cable fly needs a cable station, so for most people it’s a gym exercise. Pec deck needs a machine, so for most people it’s a gym exercise.
About the same: both rate Excellent for joint and recovery cost in our research rubric.