Charles Glass says the drag curl can be one of the best biceps builders — but most people do it wrong. He argues the movement’s power comes from keeping tension, not from swinging or ego-loading.

Next, Glass watched dozens of trainees perform the curl and noticed the same flaws repeating. Those mistakes shift work away from the biceps and into the shoulders and momentum.

Then, he posted a short video demonstrating the correct bar path, elbow motion, and top contraction. His corrections are simple, but they change what muscle takes the load.

Finally, when lifters apply Glass’s cues they feel the biceps more, get a stronger peak, and avoid letting the front delts steal the set. He says that’s how you build shape, not just numbers on the bar.

 

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Charles Glass Reveals Common Drag Curl Mistake and How to Fix It for Better Biceps Growth

Glass summarizes the core error in one line: the movement becomes a rocking motion that kills contraction and robs the biceps of tension. He wants the lifter to drag the bar, keep the elbows back, and squeeze.

“Are you doing drag curls? Give this bicep movement a try and watch them grow!”

He shows that many people lean, swing, or allow the bar to arc away from the torso. That arc unloads the muscle at critical points and undermines time under tension.

“We want more of the contraction on the biceps. So what we’re trying to do is focus mainly on the belly of the biceps. Because what happens is most people do this: they are rocking back and forth. But you’re not doing anything.”

Glass stresses that the fix is not heavier weight. It’s a disciplined bar path and a strict elbow slide.

 

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How to Fix the Drag Curl Biceps — Glass’s Step-by-Step Cues by Charles Glass

Set up with a straight bar or EZ bar and a shoulder-width supinated grip. Keep the torso upright and the chest proud. That position creates a stable frame to move the arms from.

Second, pull the elbows back as you drag the bar up your body. Think of the bar sliding close to your torso. That forces the biceps to shorten under load and removes shoulder assistance.

“When you do a good drag curl, you’re pulling up and into, pulling the elbows back, that’s all biceps. Look, you can see right there, all biceps work.”

Third, lock the shoulders down and squeeze at the top. Hold the finish for a beat to maximize the peak contraction before lowering controlled.

“See how you lock the shoulders down. Now, it’s all biceps. You hit the brachialis a little [as well].”

Glass recommends moderate weight, strict reps, and a controlled tempo. He says the movement should feel short, brutal, and unmistakably biceps-driven.

Why This Fix Works

Dragging the bar and keeping the elbows back keeps the load where it belongs — on the biceps short head and brachialis — for a full range of contraction. That invites structural shape improvements, not just size.

Next, the closed bar path preserves tension at the top and bottom of each rep. That sustained tension increases time under load, the primary driver of hypertrophy.

Finally, the strict finish and the brief hold at peak teach the mind–muscle connection. When you feel the biceps work instead of the shoulders, you recruit the right fibers and improve long-term development.

Charles Glass correction to the drag curl Biceps is straightforward and highly effective: stop rocking, pull the elbows back, drag the bar close, lock the shoulders, and squeeze. Those cues — not heavier plates — force the biceps to do the work and deliver better shape and peak. Apply the changes for a few weeks and the difference becomes obvious: tighter contractions, fuller peaks, and more reliable arm gains.