Kill the momentum with a top pause, all biceps no swing.
Elbows stay pinned, the pause exposes any cheating so stay strict.
Stopping the bar at the top strips out the momentum that carries most curls through their weakest point, leaving the biceps to hold a full contraction with nowhere to hide. Every rep becomes a lift plus an isometric squeeze, which adds time under tension without adding weight. It earns its spot when your curls have gotten faster than they have gotten stronger.
A genuine one second, long enough for the bar to be completely still. Counting a quick bounce as a pause defeats the purpose. If you cannot hold it motionless, the weight is too heavy.
The top pause locks in the peak contraction and exposes swinging, since a swung rep cannot hold still up there. Bottom pauses have their place for killing the stretch reflex, but this variation is about owning the squeeze.
Expect to drop the load noticeably, because you have removed cheat momentum and added an isometric to every rep. Treat it as a strictness upgrade, the smaller number on the bar is doing more work for your biceps.
