Exercises / Rear Delt Fly

Rear Delt Fly

The rear delt fly is a dumbbell isolation movement that trains shoulders first, with back as secondary. Default rest between sets in the app: 60 s (1 min).

Also called: reverse fly, bent-over lateral raise.

frontbackPrimaryShouldersSecondaryBack
Fig. Rear Delt Fly: primary muscle shoulders, secondary back — as tagged in the Zyra Workouts exercise catalog. Regions are schematic (one block per catalog muscle group, not anatomy); which muscles a lift loads most also depends on technique and range of motion.
Primary muscle
Equipment
Dumbbell
Type
Isolation
Default rest
60 s

Rep and RIR targets by goal

These are the sets the Zyra Workouts program generator writes for a isolation exercise under each goal. RIR is reps in reserve — how many more reps you could have done when the set ended. A default the app starts from, not a prescription.

GoalReps per setRIRRep ceiling
Strength6829
Hypertrophy1015114
General812212

How progression steps on Rear Delt Fly

The app moves the load on Rear Delt Fly in steps of 2 kg — the fixed step the app uses for dumbbells, machines and cable stacks. The rule is the same for every exercise: the rep ceiling is the midpoint of the rep range plus the RIR target (for the hypertrophy row here, 10–15 reps @ RIR 1 → ceiling 14). Clear the ceiling and the next set is one step heavier at the bottom of the range; fall under the range floor and it backs off one step; anything between holds.

Worked example, in the app's words: Last time 25 kg × 15 · target 10–15 @RIR 1 (ceiling 14) → +3 kg → 28 kg × 10.

Alternatives

Tools for this exercise: Rear Delt Fly 1RM calculator · Rear Delt Fly load chart (% of 1RM)

Frequently asked

What muscles does the rear delt fly work?

In the Zyra Workouts catalog the rear delt fly is tagged with shoulders as its primary muscle and back as secondary. The app counts a primary set as one set for that muscle and a secondary set as half a set. Which muscles a lift loads most also depends on technique and range of motion.

How many reps and sets for the rear delt fly?

The app's program generator sets 6–8 reps @ RIR 2 for strength, 10–15 reps @ RIR 1 for hypertrophy, 8–12 reps @ RIR 2 for general — the isolation rule, 2–4 sets depending on goal and experience. These are the generator's defaults, not a prescription; a coach can adjust them to you.

What can I do instead of the rear delt fly?

The app's swap ranking (same primary muscle, then feasible in your gym, same type, same equipment) offers Lateral Raise (Dumbbell), Face Pull, Lateral Raise (Cable) and Arnold Press. All train shoulders first.

Muscle groups

Primary
Secondary
  • Back — counts as half a set

Related exercises

Other shoulder isolation movements in the catalog:

Browse all 61 exercises →

Guides for Rear Delt Fly

Log it in Zyra Workouts

Zyra Workouts logs your sets on the rear delt fly, applies this progression rule to suggest the next load, and counts the work toward your weekly sets per muscle — offline-first, on iOS. It is in development and not yet on the App Store.

Not yet on the App Store — about Zyra Workouts

Zyra is a training and nutrition tracking tool. Nothing on this page is medical advice, a diagnosis, or an individual prescription. The numbers are estimates from published formulas and the apps' own rules — consult a qualified professional for decisions about your health, and a coach for your training.