Extend the set, extend the pain, extend the growth
Some may think doing supersets for biceps is somehow less intense because you’re saving something for the second movement, but I assure you that how I do them is plenty intense. Rather than thinking of them as supersets, which many people associate with antagonist muscle groups, think of these as “extended sets” or mechanical dropsets.
Here’s how built my biceps routine. Similar to how I trained shoulders, I do the first movement of each pair in in super-strict fashion, usually a curl from the seated position so that there’s almost no body English. Oftentimes, I can’t reach the rep target of 15, and start doing rest-pause reps to finally get there.
But that doesn’t mean the set is over. With all that accumulated fatigue, I now stand up and complete another 15 curls. The standing position allows me to recruit other assisting muscle groups and to extend the set. Have you ever noticed you can use more weight on standing dumbbell curls than when you’re seated? This superset takes advantage of exactly that mechanism. I’m thus going way beyond the point at which I’d normally end a set.
Though the rep range is high at 15, rest assured, I’m still going very heavy with those 15 repetitions, and I may reach failure well before that. If I do, I’ll rest-pause my ass off till I get to 15. I’m going heavy, explosive, and forcing every muscle fiber to contract.