Bigger Arms


Undersun Fitness

- 6 July

Learn how to build bigger arms anywhere without sacrificing gains with these muscle-building exercises using only resistance bands.

To build the biggest biceps possible, you need to do curls – essentially the only isolation movement there is for biceps – on a regular basis (at least once a week).

But you know what’s NOT necessary for building bigger guns? A commercial gym. Dumbbells. A barbell. A cable station. A power rack.

All of these things are well and good, BUT if you’re unable (or unwilling) to get to the gym and still want to build shirt-stretching biceps, you can do it at home, on the road, or even on the beach with one portable and inexpensive piece of training equipment…


It’s not hype. It’s the truth. Your muscles don’t know the difference between resistance provided by a free weight (barbell or dumbbell) versus a fitness strength band. And these resistance bands, in particular, provide all the tonnage you need – hundreds of pounds of resistance total, with five different sizes of bands – to spark muscle growth in even the most stubborn pair of biceps.

In the below article and accompanying video featuring Undersun’s Founder and Chief Fitness Officer, James Grage, you’ll see how to train every aspect of the biceps for maximal growth and ultimate efficiency.

No more having to navigate a crowded, expensive gym just to get in a workout and build some serious muscle. With resistance bands, you’re always steps away from the gym, even at the beach! 


Ever notice how many different types of biceps curl exercises there are? If you’ve spent time at a commercial gym or read any number of fitness magazines, you know what we’re talking about.

You’ve got standing curls, preacher curls, reverse curls, incline curls, just to name a handful of the most common types. All of these should be utilized in your training program to maximize hypertrophy (muscle size) in your biceps – but not just for the sake of variety or “muscle confusion,” a term many so-called training “experts” like to throw around.

There’s actually a legitimate reason to use all these different curling variations, and it all comes down to arm position and the particular area of the muscle that’s targeted with each.


With biceps, you’re talking about three different arm positions (specifically the upper arms, as the forearms will move during the curling movement):

  • Arms in line with the torso (as with a traditional standing barbell or dumbbell curl, or a seated dumbbell curl)
  • Arms in front of the torso (as with a preacher curl, whether it be with a barbell, dumbbell, cable, or specialized machine)
  • Arms behind the torso (as with an incline dumbbell curl or behind-the-back cable curl)

These three arm positions all target different parts of the biceps. (Remember, the biceps brachii muscle is made up of two different heads, hence “bi”: the long/outer head and the short/inner head.)

When the arms are in front of the torso (ie, preacher curls), more emphasis and tension is placed on the short head.
When the arms are behind the torso (incline or behind-the-back curls), the emphasis is placed on the long head. Keep in mind, the long head is what makes up a majority of the biceps “peak” that so many people covet.
When the arms are in line with the torso (ie, standing barbell curl), the short and long heads are targeted more or less equally. Because of this, these variations are generally considered the best overall mass-builders and often allow you to go heavier than the other two arm positions.


Aside from the upper arms, you also have forearm/wrist rotation. The three types of curls (arm positions) just mentioned typically involve supination of the forearms, where the palms and forearms face upward during the curling motion.

The opposite of supination is pronation, where the palms and forearms face downward. This position is more commonly called a reverse grip, with the exercise referred to as a “reverse curl.”

Reverse curls still hit the biceps, but they also bring the brachialis and brachioradialis muscles into play to a greater extent. The brachialis runs below the larger biceps brachii and provides thickness to the upper arm. The brachioradialis, on the other hand, is more of a forearm muscle (although it does attach above the elbow as well). As a result, reverse curls are ideal for hitting both the biceps and forearms with one movement.


Here’s the thing with doing curls with free weights (dumbbells and barbells) and even cables: To hit all the different angles and arm positions for maximal growth, you need to utilize a number of other pieces of equipment – namely, a preacher bench and incline bench. Otherwise, you won’t be able to achieve the desired arm position while still curling against gravity.

Now, here’s the thing with doing resistance band bicep exercises: You can do all of the aforementioned curling variations with no additional equipment. You can do preacher curls without the preacher bench, incline curls without the incline bench, reverse curls without an EZ-bar.

With bands, exercises are done either anchored or unanchored. Anchored exercises require an additional stable structure to attach the band to or loop it around, but any number of landmarks in your house or on your property will do the trick.

A doorway is one such anchor point. Purchase the Undersun Resistance Bands Combined Outdoor and Indoor Anchor, and most any door can be your gym. Other possible anchor points include a sturdy bed post, a stop sign or lamppost outside, or a pillar on your patio.

With elastic bands, your line of pull doesn’t have to be against gravity (vertical) like it does with free weights, so your anchor point can be out in front of you or even overhead. With band preacher curls, for example, you pull horizontally and still get maximum tension. (See below photo and description of band preacher curls.)

Now, let’s move on to a great resistance band arm workout for mass…


The following bicep exercises with resistance bands are the same ones demonstrated by James Grage in the above video. Below, you’ll find written how-to descriptions for each move, plus recommend sets and reps.

All four exercises can be done in one workout for a complete workout that hits all angles and both biceps heads, in addition to forearm work via reverse curls.

The sets and reps for all exercises in this resistance band bicep workout use Grage’s hallmark 20-10-10-15 scheme on each exercise to maximize hypertrophy:

  • Set 1: A slow and controlled 20 reps.
  • Sets 2 and 3: 10 reps with additional weight. With these extra-heavy sets, adjust the resistance as necessary to complete the full number of reps.
  • Set 4: 15 explosive reps to work fast-twitch muscle fibers. Drop the weight back down to match the 20-rep set (Set 1). Performing the last set in double time burns out your muscles to achieve maximum pump.
  • Rest: 90 seconds between each set.
The Perfect Muscle-Building Rep

To maximize hypertrophy, your total “time under tension” (TUT) on each set needs to be at least 30 seconds, up to a minute or even more. To achieve this TUT, each rep should take 3-4 seconds, performed in this manner:

  • 1 second on the concentric (positive) phase of the rep
  • ½ second to 1-second squeeze at the top of the rep
  • 2 seconds on the eccentric (negative) phase of the rep

Biceps Exercise 1: Standing Band Preacher Curl

Target: Short head of the biceps

Band Weight: Medium

  • Anchor the band to a stable structure in front of you at around shoulder height. Grab the band in both hands, with your palms facing up (supinated).
  • Start with your body upright, core tight for stability, and your arms extended and parallel with the ground. Make sure there’s tension on the band from the start; if it’s loose, step back to increase resistance.
  • Keeping your upper arms stationary (parallel with the ground), curl your hands toward your face.
  • At the top of the movement, turn your pinkies up and out (supination) and squeeze for peak contraction.
  • Slowly reverse the motion to return to the start position, then repeat for reps.

Biceps Exercise 2: One-Arm Standing Behind-the-Back Band Curl

Target: Long head of the biceps

Band Weight: Medium

  • Anchor the band to a stable structure at around hip height.
  • Grab the band in one hand, and turn around to face away from the anchor point.
  • Start with your body upright, feet staggered for stability (same leg back as the working arm), core tight, your working arm behind your torso, and tension on the band.
  • Keeping your upper arm (elbow) behind your torso throughout (don’t let it move forward), curl your hand up toward your shoulder.
  • At the top, turn your pinky up and out and squeeze the contraction.
  • Slowly reverse the motion to return to start, complete all reps on that arm, then switch arms and repeat.

Biceps Exercise 3: Band Reverse Curl

Target: Brachialis and brachioradialis

Band Weight: Light

  • Stand on the band with both feet to “anchor” it to the ground.
  • Start with your body upright, core tight, and arms extended at your sides with your forearms and palms facing behind you (pronated).
  • Keeping your upper arms fixed at your sides, curl your hands toward your face, maintaining the pronated forearm/wrist position (reverse grip).
  • Squeeze the peak contraction in the biceps and forearms at the top, then slowly lower back to start. Repeat for reps.

Biceps Exercise 4: Standing Band Biceps Curl

Target: Long and short heads of the biceps

Band Weight: Heavy to X-Heavy

  • Anchor the band to a stable structure as low as possible (ground or floor level).
  • Grab the band in both hands with your palms facing forward (supinated).
  • With your body upright, lean back slightly with a staggered stance to increase tension on the band; your arms should still be more or less in line with your torso.
  • Keeping your upper arms stationary (at your sides), curl your hands toward your face. At the top of the movement, turn your pinkies up and out (supination) and squeeze for peak contraction.
  • Slowly reverse the motion to return to the start position, then repeat for reps.