I dig those supersets, Bao, I was doing a lot of them before I started the DC program, and I will go back to them again.
For a variation, try doing supersets 1 workout for the same, rather than opposing, bodyparts.
i.e., Pulls up to failure immediately followed by bent over rows (adjust the weight for fatigue).
Incline dumbbell bench straight into dips.
Etc....
I like the sets you are doing, I just change them up sometimes (to two exercises for the same bodypart) to keep mind and body fresh.
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