High Reps Light Weight Or Low Reps Heavy Weight For Biceps: Which Is Better To Build Bigger Arms?

Small muscle groups like the biceps need to be trained slightly differently, compared to larger muscle groups, to achieve maximal hypertrophy. This post explains whether it’s better to lift high reps with a light weight or low reps with a heavy weight to grow bigger biceps.

It is better to train the biceps by lifting in a high rep range and using a lighter weight for isolation-type movements like the dumbbell curl. In contrast, lifting in a low rep range and using a heavier weight is ideal for compound pulling movements like the row and chin-up.

When I was a skinny dude, I failed to build bigger biceps because I was either lifting too heavy or too light.

Neither method worked.

It was only when I started applying the perfect rep range and weight load that my arms started growing.

Below, I explain the ideal way to train your biceps.

Let’s go!

Definition Of High Reps And Light Weight

Generally speaking, performing 10-15 repetitions per set, or more, is considered to be a high rep range for biceps. This rep range is typically completed using a weight that is 75-50% of the lifter’s 1-repetition maximum (1RM). A high rep range is ideal for isolation exercises like the bicep curl.

This is an important term to define.

Why?

Discrepancies are common regarding what is considered to be high/low reps and heavy/light weights.

For example, the number of reps considered to be “high” is often much lower in the bodybuilding and strength training community, compared to that of the HIIT and general fitness community.

We will be using bodybuilding terms for the purpose of this post.

Here, the standard term for “high reps” is defined as 10-15 repetitions per set performed at a weight that is 75-50% of the person’s 1-rep max.

A 1-rep max refers to the heaviest amount of weight you can lift for a single repetition. The lower the rep number the heavier the weight should be. You can find your 1RM estimates on Strength Level here.

High reps performed at lighter weights are generally good for activating a combination of fast-twitch and slow-twitch muscle fibers.

“Fast-twitch fibers support quick and powerful movements whilst slow-twitch fibers support endurance activities. Fast-twitch fibres are more responsive to hypertrophy”.

Stacey Penney, NASM PT.

Therefore performing high-rep training is great for both strength and size gains (hypertrophy), as well as endurance gains.

Bodybuilders will often perform isolation exercises like the bicep curl and its variations in the high-rep range.

Definition Of Low Reps And Heavy Weight

Generally speaking, performing 6-9 repetitions per set, or less, is considered to be a low rep range for biceps. This rep range is typically completed using a weight that is 85-80% of the lifter’s 1-repetition maximum (1RM). A high rep range is ideal for compound exercises like the barbell row.

In bodybuilding terms, the standard term for “low reps” is defined as 6-9 repetitions per set performed at a weight that is 85-80% of the person’s 1-rep max.

Unlike high rep ranges, performing low reps using a heavier weight is ideal for activating fast-twitch fibers only.

This makes low-rep training ideal for building bigger and stronger muscles.

Most people will perform compound exercises like the pull-up, chin-up, row, bench press, squat, etc in the low-rep range.

Best Bicep Rep Range For Different Goals

Here’s how different reps and weight loads can be used to achieve different biceps-building goals.

Below, I’ll explain why the recommended reps and weight works to increase biceps size and strength.

You can check out my other post if you’re unsure which rep ranges are best for different training goals.

Do Biceps Respond Better To High Or Low Reps?

The biceps generally respond better to high rep ranges performed at a lighter weight. However, it is important to always use a weight that challenges the user. Additionally, it is essential to apply progressive overload by increasing weight over time to keep the biceps challenged for growth.

In accordance, 89% of the responses in this Quora thread agreed that high reps are ideal for optimal biceps growth.

And of those who advocated for high-rep training, a further 56% said that a combination approach is best to increase biceps size

Put simply- the majority of Quora users advise a combination approach.

Here, you’d perform both high reps at a lighter weight AND low reps at a heavier weight.

In other words, cycle between the high and low rep ranges (find the details at the end of the post)

For example: you could work in the 10-15 rep range using a lighter weight in month 1, switch to a 6-9 rep range using a heavier weight in month 2, and repeat the process over again.

But the important thing is to not use “lighter lifting” as an excuse to lift light weights.

The keyword to stress here is “lighter”.

At the end of the day, building biceps size and strength requires you to lift a weight that challenges your biceps.

And to sustain bicep gains, you should also be progressive overloading (increasing intensity over time).

For most people, adding weight is the easiest way to progressive overload.

How much you overload our biceps will vary from person to person and is dependent on factors such as age, gender, strength levels, genetics, and previous training history.

Why Lifting Light Vs Heavy Weights Is Better For Biceps Growth

Generally speaking, it is better to lift lighter weights at high reps to promote biceps growth. The lighter weight allows an individual to lift with better form, a greater range of motion, and practice time under tension. These are 3 factors that contribute to biceps growth.

You can see it’s generally better to train your biceps with higher reps using a lighter weight.

Take a bicep curl for example.

By using a lighter weight, you can curl with better form and maximize the range of motion (ROM).

ROM describes the extent to which the weight travels relative to your joint.

In a dumbbell curl example, a full ROM requires you to fully extend the forearm and allow the dumbbell to reach the lowest point before being curled back up.

Lifting with a full ROM improves your mind-muscle contraction and allows for more time-under-tension (TUT).

It also allows you to squeeze your biceps at the peak of the curl and get a better pump.

Furthermore, most people can only achieve a full ROM on isolation-type moves like the bicep curl by reducing the weight.

Consequently, lifting lighter weights at higher reps is generally better to stimulate growth in smaller muscles like the biceps.

But that’s not to say lifting heavier weights at low reps doesn’t benefit biceps growth either.

Doing heavy reps at low reps once in a while can be beneficial for increasing biceps strength.

But if your goal is to build bigger biceps, then you should focus primarily on working at higher reps with a light weight (10-15 reps at 75-50% 1RM).

Drawbacks Of Lifting Heavy Vs Light Weights For Biceps Growth

It is not generally recommended to lift heavy weights for bicep curls when the goal is to promote maximal biceps growth. Lifting too heavy a weight makes it difficult to maintain good form. As a result, neighboring muscles may be recruited and this reduces biceps activation.

We’ll be using the bicep curl example again.

Here, lifting too heavy a weight often causes your form to break down.

Ever seen someone trying to curl a 50lb+ dumbbell?

They’ll often resort to swinging their hips too and fro, and use the momentum generated to help them lift the weight.

This is called a “cheat curl”.

There can be a time and place for cheating.

Bodybuilders periodically do cheat curls to increase biceps strength.

But it needs to be performed correctly to be beneficial.

Most beginners will do it incorrectly, and as a result, they transfer biceps activation to the shoulders, hips, abs, and legs.

Consequently, the biceps receive very little stimulation at all.

Therefore the disadvantages of lifting heavy at low reps generally outweigh the benefits it provides.

It is instead better to just lift a lighter weight at higher reps in a slow and controlled manner.

You might also be interested in my other article to find out the Ideal weight for bicep curls.

Should You Lift Heavy Or Light For Better Biceps Growth?

Generally speaking, the average beginner should lift a lighter weight using higher reps to build bigger biceps. However, this only applies to isolation-type movements such as the bicep curl. Compound pulling movements should be performed with heavy weights using lower reps.

As mentioned previously:

Light bicep curls allow you to maximize biceps activation vs heavy curls because a lighter weight allows for a greater ROM, controlled lifting, and a greater biceps pump.

However, lifting light weights at high reps will provide little benefit when it comes to compound pulling movements (which are also awesome bicep builders).

I’m talking about exercises like the row, pull-up, and chin-up.

These movements primarily work the back, but also work the biceps indirectly.

And since they engage so many muscle groups in one go, it’s generally better to go heavy using low reps.

By doing these heavy compound movements, you can even build your biceps without biceps curls as long as you’re completing enough sets per week.

I only performed heavy compound pulling movements in my first year of training. And this was enough to grow my biceps by an inch.

Now, I’m not saying curls are useless because they’re not.

The most effective bicep-building program will combine light weight curling (using high reps) WITH heavy weight pulling (using low reps).

You may also want to check out my other post to find out how many exercises you need for biceps growth.

The Biceps-Building Combination Approach

Taking everything together, here’s how I train my biceps using a combination approach.

This training method allows you to work your biceps with high-reps/light-weight as well as low-reps/heavy-weight.

Asa result, you’ll maximize biceps hypertrophy AND strength gains.

Here’s how to structure the perfect biceps workout program as a beginner-intermediate:

Aim to complete 10-15 direct biceps sets per week.

This target can be met in 3 ways:

1. 10-15 sets of isolation-type movements like the curl which train the biceps directly.
2. 20-30 sets of compound-type movements like the row, pull-up, and chin-up which train the biceps indirectly.
3. Combination of both.

As a general rule, 2 sets of indirect biceps work is the equivalent to 1 set of direct biceps work.

I call this the rule of halves.

So you can play around with different combinations to reach your 10-15 total direct biceps sets per week.

Here’s an example combination:

You can also apply periodization training principles to further optimize biceps growth and strength gains.

To do this, you would work on the above-specified sets, reps, and weight for one month.

Then in the next month, you would decrease the reps and increase the weight for all exercises.

For example: instead of doing 4 sets of 12 reps on bicep curls, do 4 sets of 8 reps (and increase the weight accordingly). And instead of 4 sets of 8 reps on pull-ups, do 4 sets of 6 reps instead.

By cycling through different rep ranges in this manner, you can capitalize on all aspects of biceps gains (strength, size, and mass).

Periodization will also help you to break strength plateaus and progressive overload your biceps more efficiently.

You may also be interested in my other post for more detail on how many sets and reps you should do for bigger biceps.

How To Train Your Biceps At Home

Adjustable dumbbells are ideal for home biceps workouts.

That’s because they contain light AND heavy settings in a single dumbbell unit. And this allows you to hit your biceps with light isolation-type lifts as well as heavy compound movements.

I use the Powerblock Elites (you can find the cheapest price here).

They aren’t the cheapest dumbbells on the market but they are, in my opinion, one of the best-value dumbbells.

The Powerblocks are ideal for biceps workouts.

Not only do they have both light and heavy adjustments, but the small 2.5/5lb increments are perfect for overloading on isolation lifts like the curl.

Think about it.

It’s much easier to add 2.5lbs to your dumbbell curl every week than it is to add 10lbs in one go right?

Trust me, these baby’s are all you need to build bigger arms at home.

If you have 9 square feet of space and the budget for it, then a pull-up tower like this Sports Royal Tower also allows you to do chin-ups and pull-ups.

A cheap doorway bar like this Prosource bar can also do the job.

Just be aware that a doorway bar often scratches and damages your doorframe (speaking from personal experience).

I also use a chained belt like this DMoose weight belt to attach the Powerblocks to my waist to increase resistance.

This gives me a better biceps pump.

A belt isn’t essential.

You can just hold the Powerblocks between your legs.

But the Powerblocks have an awkward shape (one of their main disadvantages) that can make it difficult to get a firm grip when held between the legs (unlike a traditional dumbbell shape).

This makes a chained belt handy for this application.

Conclusion

I explained whether it’s better to lift high reps with a light weight, or low reps with a heavy weight, for optimal biceps growth.

You should primarily focus on a higher rep range for isolation-type exercises like the dumbbell curl.

This allows you to concentrate on targetting the biceps with good lifting form and a full range of motion.

In contrast, compound pulling exercises like the row, pull-up, and chin-up are more suited for a lower rep range.

This allows you to load more weight and drive strength gains.

You may also periodically lower the rep range (and increase weight) for both types of movements to drive further strength gains.

This allows you to achieve the greatest progressive overload and achieve maximal hypertrophy.

What rep range will you be training your biceps with?

Let me know in the comments!

You may also be interested in the downloadable Kalibre Blueprint PDF which details exactly how I gained 40lbs of lean muscle (it’s 100% free!). It details the exact exercises and nutrition I used to go from skinny to ripped!

Thanks for reading guys!

Peace Out,

Kal

(Biochemistry BSc, Biomedical Sciences MSc, Ex-Skinny Guy)