Pec Deck Isolation Exercise

Get swole with four sets—each executed differently—of this isolation move

Single-joint movements are normally done last in your training session because they better isolate the target muscle with relatively lighter weight and allow you to finish with a really good muscle pump. What if I told you we can instead get a truly monster pump on your final exercise on chest day? Then follow me to the pec deck machine.

I like the pec deck over other cable and dumbbell flyes because the angle in your elbows is automatically locked in position, which can be difficult for some lifters to maintain, especially when training to failure, as in this sequence.

What’s different here isn’t the exercise but how you’ll do it. Each of the 4 sets is done slightly differently from the others, with extra emphasis on the inner-pec region.

SET 1: It’s critical that you’re using the right weight, so the first set is about ensuring both the seat height and weight are set correctly. You want to be using a weight with which you fail at 10 to 12 reps, using a smooth motion. My preference is to keep my shoulders, elbows, and hands (check the mirror) in the same horizontal plane for the greatest efficiency. Adjust the load as necessary to ensure you fail within the target rep range.

SET 2: Here’s where things start to get interesting. On the second set, hold the peak-contracted position for a full second—with everything else being the same—which requires an isometric contraction at the top rather than allowing the weight simply to return your hands back to the start. This is more challenging for the inner-pec fibres and a step up in difficulty than the previous set. Do as many as you can, but aim for 10.

SET 3: Here, you’ll alternate full-range reps with quarter reps (at the top of the range of motion). Do a full rep, but instead of going all the way back, let the weight pull your hands just 18 inches apart and then complete a quarter rep. One full and quarter rep equals one rep, so you’re alternating 10 full plus 10 quarters, and that counts as 10 reps. The last ones should be especially tough, and use your spotter to help you reach 10. In my experience, many trainers take those quarters too far back into half reps, so try to control the negative to limit the separation of your hands to about 18 inches.

SET 4: On the last set, you’ll repeat the first set—a normal set of 10—but then smash out as many quarter reps as possible. I’ve done as many as 30 quarters, but simply keep going and do as many as you can before your partner steps in and helps you do even more. You’re going to take your inner pecs to total failure. You can even use a faster speed and a little momentum if you need to.

The pump is tremendous, and the next-day soreness exceptional. I don’t know many guys who don’t want to make those inner-chest fibres pop out a bit more, so here’s your chance to make it happen.

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