Like all supersets, this method involves doing two exercises performed back-to-back with minimal rest. But here, the first exercise is a major lift done with a partial range of motion and the second is an isolation exercise.
How you do your partial reps is important. You need to keep the target muscles under tension for a long enough period of time, so perform the partial reps in a "no-acceleration" style. Here's what it looks like for delts:
Partial-Rep Shoulder Press + Lateral Raise
Try to maintain the same fairly slow speed during the whole range of motion, focusing on keeping the tension on the target muscle. It should take you about the same time to complete one partial rep as it would a full rep. Do 8-10 reps on both the partials and the isolation exercise.
Not Just for Delts
This same training method can also be used for:
- Pecs: Do the bottom-half of the bench press for partials, then do the cable cross-over for isolation.
- Quads: Upper half of squat, then leg extension
- Hamstrings: Middle portion of a Romanian deadlift (from below the knees to mid thigh), then leg curl
- Lats: Second half (contracted position) of a lat pulldown, then straight-arm pulldown
- Biceps: First half of a chin-up or lat pulldown, then barbell curl