Single-arm bench press variations are typically done in one of two ways:

  1. Use just one dumbbell and do all the reps on one side before switching to the other side.
  2. Grab two dumbbells and do the reps in alternating fashion: right, left, right, left, etc.

While both versions work, for a little extra pec demolition, try this challenging option:

One-Arm Bench Press With Iso-Hold

Using two dumbbells, press with one arm while holding the other arm at approximately a 90-degree angle. Repeat in reverse on the other side in one continuous set.

You want the non-pressing arm to be bent approximately 90 degrees, which puts the dumbbell a few inches off the chest, forcing the pec on that side to contract hard the whole time. I prefer a neutral grip.

When To Do Them

Do these after you've finished your other pressing for the day: 1-2 sets of 5-8 reps each side. Lower reps tend to work better because otherwise it requires dropping the weight to embarrassingly low levels, which studies have shown can be extremely detrimental to the ego.

As a bonus, there's also a substantial demand on the core to keep your torso steady, so you don't want to get greedy by going too heavy and end up flopping off the bench.

Related:  7 Brutal New Upper Body Exercises

Related:  Build Your Chest With This Combo Exercise