Should You Do Bicep Curls One Arm at a Time? (4 Things You Should Know)

Last updated on October 31st, 2022 at 06:15 pm

Who else wants to know, “Should You Do Bicep Curls One Arm at a Time?”

When it comes to dumbbell bicep curls there are a wide variety of exercises you can use.

Some people prefer to curl both dumbbells at the same time, almost mimicking a barbell bicep curl.

And then again, there are those who prefer to curl one arm at a time.

But, is one way better than the other?

Let’s find out.

Should You Do Bicep Curls One Arm at a Time?

Performing bicep curls one arm at a time is better for muscle gains. It allows you to concentrate solely on both the concentric and eccentric part of the movement. Furthermore, your “resting” arm will keep the tricep flexed for full extension, while providing a stretch in the bicep. This is ideal if you’re looking to build bigger arms. It is also likely that you’ll reach failure quicker when bicep curling with both arms at the same time.

1. One Arm a Time is Better For Muscle Gains

The debate about whether curling with one arm at a time or both has been raging on forever.

And there are people firmly in both camps that believe one way is better than the other.

However, I am of the belief that if your aim is to build muscle then doing bicep curls one arm at a time is the way forward

This is not to say that you can’t build muscle by bicep curling both arms at the same time.

Of course you can.

If you apply resistance to a muscle it has the potential to grow.

However, I would typically perform two-armed bicep curls as part of a circuit or a workout more geared towards fat loss.

You require more core stabilization with two-armed curls.

This actually goes slightly against the grain with most one-armed exercises.

If you were to dumbbell bench press or overhead press with just one arm at a time, your core would be activated to greater effect.

This is simply to stop you from rolling over or leaning too much to one side.

But, it seems to work the other way round with dumbbell biceps curls.

As I say, I believe bicep curling with one arm at a time is far better in terms of muscle gain, and I’ll explain why this is now.

2. Alternating Bicep Curls Allow You to Focus Better

When it comes to alternating bicep curls I feel that you can focus much better by totally concentrating on one bicep at a time.

This gives you the opportunity to really control both the concentric and eccentric portion of the lift.

In effect, when you curl both arms at the same time with dumbbells your concentration is divided between the two limbs.

It may not seem like much of a difference, but it certainly does have an impact.

Plus, single-arm alternating curls allow you to overload the movement more, as well as allowing for heavy negatives.

Both of these factors play a crucial role in muscle growth.

Now, many people will argue that the single-arm bicep curl allows one arm to “rest”.

But, in truth I don’t really see this.

You still have to grip the dumbbell, the tricep of the non-working arm remains flexed while in full extension, and the bicep is stretched (more on this in a moment).

Trust me, when I say that any “rest” that you’re getting is absolutely minimal.

I know that there are those that will perform single-arm bicep curls with the non-working arm in a position that contracts the bicep more.

This involves performing all your reps on one side, while the other arm is bent at the elbow so that the lower arm is parallel to the floor.

You then perform your reps on the other side in the same manner.

So, this way you are performing an isometric contraction of the bicep – one bicep prior to performing your reps and the other one afterwards.

I see no problem with performing your bicep curls in this manner.

That being said, even if you perform alternating bicep curls the conventional way I don’t believe that you’re losing out because one arm is “resting”.

Alternating Bicep Curl With Isometric Hold

3. Your Biceps Will Get a Better Stretch at the Bottom

When it comes to bicep curls we all typically aim to contract the bicep at the top of the movement.

However, having the bicep in a stretched position at the bottom is just as important for muscle gains.

So, you should always take your biceps through the full range of motion.

That being said, I often see people not bringing their arms all the way down when performing bicep curls.

And this is especially true when you perform curls with both arms at the same time.

I know that you may think that this applies constant tension to the bicep, but as I say the stretch position at the bottom is just as important as the contraction at the top.

In fact, one of my favourite bicep exercises is the seated incline dumbbell bicep curl.

There is no better bicep exercise for getting that stretch.

And this is typically one exercise when you really feel the burn in the biceps.

That being said, I do prefer to do seated incline curls with both arms at the same time.

Okay, this goes against much of what I’ve said, but your upper body is braced against the bench.

This means you are less likely to sway when performing two-armed curls and you can still isolate the biceps.

However, when it comes to conventional standing dumbbell curls I would revert to alternating.

So, by performing your curls one arm at a time you can ensure you hit this stretch throughout your set.

4. You Will Fail Quicker When You Curl With Both Arms

The other thing about curling dumbbells with both arms is that you will typically come to failure quicker.

In fact, you usually won’t be able to curl as much weight as you do with the alternating variety.

Admittedly, there may not be a massive difference in weight, but it’s probably enough to make a difference.

Two arm bicep curls require more core stabilization, plus it takes more energy to use both limbs at the same time.

This is why I prefer to perform two-armed curls as part of a circuit.

So, if I’m completing a circuit or a more conditioning-based workout then I’m more likely to curl with both arms at the same time.

Something else to consider is that because performing two-armed curls is a little harder there is more likelihood that you may cheat.

By this I mean that you are more likely to sway or use your body to get the dumbbells up.

I mentioned above that when your upper body is braced in some way you can avoid swaying and isolate the biceps more.

So, if your back is against a bench, a wall, or you’re using the preacher curl machine you are less likely to use upper body momentum to get the weight up.

However, pure and simple, if you’re performing bicep curls without any of these apparatus then curl one arm at a time for better muscle gains.

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Final Thoughts

If your aim is to build muscle then you should do bicep curls one arm at a time. This allows you to focus on both the concentric and eccentric part of the movement, thus meaning that you isolate the biceps better. You can also overload the biceps and perform heavy negatives when using just one arm. Furthermore, alternating biceps curls allow you to stretch the bicep at the bottom of the movement, which is essential for building muscle.

And to answer the next question on your mind, which I have written about, is whether it’s better to do bicep curls seated or standing.