Written by Travis Halena | ACSM CPT
Fact checked by Kirsten Yovino, CPT Brookbush Institute
FACT CHECKED
Everyone has struck the infamous double bicep pose in the mirror. It's essentially the most popular way to check and see if the stuff you've been doing in the gym has been working.
That hilltop muscle known as the biceps is not the biggest in our body, but it arguably gets the most attention. Since they are such a vital mirror muscle (hey, look good, feel good, we get it), it's essential to learn how to effectively train them.
Often biceps exercises end up being done with a form that is less than stellar as people try to increase the weight to see results. You've all seen it: the person that is swinging the dumbbells up like a full-body sneeze. While they will get some results with this method, there are better options that end up helping that prized arm muscle grow better than the rest.
Enter the concentration curl! This exercise is the premier movement to help build the biceps. But, more importantly, it also helps your mind-muscle connection, which will help achieve maximum contraction.
In this article, you will learn everything you need to know about the concentration curl, including:
- What are concentration curls?
- Muscles worked during concentration curls
- Different variations of concentration curls
- Correct concentration curls form
- Common mistakes
- Benefits of concentration curls
WHAT ARE CONCENTRATION CURLS?
Without being too obvious, a concentration curl is a specific exercise that concentrates on maximum muscle contraction with the goal of achieving muscle hypertrophy. We will go over step-by-step instructions in a bit, but for now, you need to know that the concentration curl allows your body to leverage position, so you cannot cheat on the rep at all.
It is usually done in a seated position (there are several variations), so you can lock in the rest of your body. You will rest your elbow against the inside of your leg and focus on curling the weight up toward your shoulder using just your biceps.
Why is this important? Because the body tends to want to use other muscles to assist in this motion, it often happens when you are using a sloppy form, too much weight, or if you are having a hard time connecting with the muscle as it's working. This exercise is a unilateral exercise, meaning that only a primary muscle group will be worked. If you find secondary muscle groups are also working, you're likely not using correct form.
WHAT MUSCLES DO CONCENTRATION CURLS WORK?
To get a complete understanding of the curl, you must know what muscle group you're working. So let's get familiar with that muscle on your upper arm. The biceps is responsible for flexing the elbow (bringing your hand up toward your shoulder) as well as supinating your forearm (turning your palm up). It is activated in all curling exercises, like the barbell curl, preacher curl, and spider curl.
The muscles used during concentration curls are:
- Biceps brachii: The muscle that looks like a king cobra coming up from your arm when you make your best Arnold Schwarzenegger impression. This is what we are here for today, and we will cover it for most of the article.
- Brachioradialis and coracobrachialis: Both are smaller assisting muscles. The brachioradialis is located on your forearm. It connects with the elbow joint and assists with flexing the elbow and pronating and supinating (turning your palm up or down) when the elbow is flexed. The coracobrachialis is located closer to the shoulder and assists with flexing and adducting the arm (taking away from the body).
- Brachialis: The brachialis muscle is the strongest elbow flexor in your body, and it sits in your elbow pit. Brachialis exercises are crucial for stronger upper arms.
Now, back to the money maker, the biceps brachii!
Let's dive deeper into the biceps, since it's the star of today's show. The biceps is located on the front of the upper arm between the shoulder and the elbow. Its name, by definition, should help you understand how it works. Bi means there are two heads to this muscle: the long head and short head.
Head means where the muscle attaches to. The other end attaches to the radius, the outermost of the two bones that make up the forearm (check out this article on training the brachialis). These two heads arise from the scapula and meet in the middle arm to combine and form that eye-catching boulder you're after (that's the muscle belly).
The short head is on the inner side of the arm, and the long lead is along the top/outer side. It will help to remember that long head exercises add to the peak of the bicep (mountain top) and short head exercises give it its width (sleeve filler).
Biceps Functions:
- Flexes the elbow and supinates the forearm.
- Acts as an assisting muscle in forwarding flexion (lifting the arm forward), abduction (taking the arm away from the body), and adduction (bringing the arm across the body).
- Assists in any pulling exercise you may be doing, like pull-ups, bent-over rows, and dumbbell rows.
- Stabilizes during any pushing exercise as it works opposite the triceps, such as in moves like push-ups, the bench press, and dips.
Seated vs. Standing Concentration Curl
In general, the concentration curl is done in a seated position as it creates the best way to isolate and leverage the bicep so it works almost entirely by itself. In fact, research shows that the seated concentration curl produces more bicep muscle growth than EZ-bar curls, incline curls, and preacher curls1.
It can be performed standing as well. The difference in lifting form is that standing will put you in a more "functional" position as the rest of your body will be active in the movement. When in the standing position, make sure to keep a slight bend in your knees, avoiding locking them out.
This also means you will have a lot of other moving parts to keep locked into place. If you already have difficulty feeling and concentrating (see what we did there?) on biceps during biceps exercises, the standing curl can make it even more difficult. Muscles like the glutes, spinal erectors, quads, hamstrings, and calves are now in play and must be locked into position so the body does not start to compensate. Think of them as shiny floating objects that may distract your focus when trying to isolate the bicep.
Does this mean it's an insufficient exercise? No. It just means you need to master the feeling of the seated concentration curl first as it puts you in the best position to focus on the bicep and nothing else. Once you've done that and are confident in the movement, it can be done standing.
Concentration Curl Using Cable Machine vs. Dumbbell
The exercise can be done with either of these pieces of equipment. Consider both tools in your toolbox of bicep building equipment. They are both performed in the same seated position, with the elbow resting inside the leg, and use the same muscle groups. The difference here is that the cable concentration curl will keep constant tension on the muscle.
This can be especially effective in learning to control the eccentric part (see the difference between concentric and eccentric muscle contraction here) of the exercise. That means that by moving with a slower tempo and resisting the cable as it pulls your arm back down, you're likely to feel a more significant contraction through the entire biceps.
This is generally a huge problem for people (more on that later) as they often let the weight fall on the way down instead of controlling it. It also stops the reps short of a full range of motion, leaving money on the table for growing those arms.
This is not to say the same contraction and focus cannot be felt during dumbbell concentration curls. It simply shows that, again, this will be up to personal preference. Whichever exercise you can feel the muscle working more is the one that should get some extra attention on arms day.
HOW TO DO CONCENTRATION CURLS WITH THE CORRECT FORM
Don't rush this move. Time under tension is king today. While performing it, think 3 seconds up, 3 seconds pause at the top to squeeze the muscle, and 3 seconds down. Focus on following proper form.
Concentration curls:
- Grab your dumbbell and sit down on a flat bench. Be sure to pick one that is light enough that you can control. If you start with too heavy of a weight, your body will try to cheat to curl it. Hold your weight with an underhand grip.
- Your legs will be a little wider than your hips and provide your base for this exercise. Keep your feet flat on the floor. Hinge forward, creating a 45-degree angle with your upper body. This allows you to stabilize your elbow in the correct position.
- Put your right elbow on the inside of your leg, on your right thigh. Keep that elbow in contact with the thigh during the entirety of the exercise. Use your other hand on the same leg to provide extra stability so that leg doesn't move around.
- Your arm should start straight with the dumbbell close to your lower leg, and your palm should be facing away from you. Your shoulder, elbow, and hand should be stacked in one straight line. Lock in this starting position for every single rep of this exercise. Keep your upper arm straight.
- Make sure your grip is evenly placed on the dumbbell, and squeeze as hard as possible. If your hand is tight, then everything else up the chain of your arm will function correctly.
- Squeeze your bicep as you flex your elbow and slowly bring the dumbbell up toward your shoulder. Slowly lower the weight with the same control until your arm is completely straight until you see your upper arm perpendicular. Perform desired number of reps before you switch arms, placing the dumbbell in your left arm, and resting your left elbow on your inner thigh.
COMMON MISTAKES TO AVOID
Get the most out of your concentration curls by avoiding these common mistakes.
1. Using too much weight:
A common mistake involves compromising the perfect form of the exercise and losing the extreme isolation of the bicep. Start lighter and shoot for 10-15 reps, aiming for maximum hypertrophy vs. strength. It's more important to perform this exercise correctly.
2. Losing the mind-muscle connection:
The key is right in the name. With mind-muscle connection, concentrate on the muscle and squeeze as hard as you can, just like that mirror pose. Squeeze up and down, concentrating on keeping your muscle fully contracted the entire time. Slow time under tension is the straw that stirs the drink here, not maximum strength.
3. Compensating with the rest of your body:
Make sure the elbow stays in contact with your leg and everything but your arm remains totally still. One of the goal's of this exercise is to also keep your upper arms stationary.
BENEFITS OF CONCENTRATION CURLS
Still not convinced the concentration curl deserves room in your arm-day routine? Take a look at these benefits, and you'll be curling like crazy!
1. Concentration curls are an isolation move:
Concentration curls provide the most isolation of the biceps, leading to toned, bulging arms anyone would be proud of.
2. It improves your performance during other exercises:
A bigger, more muscular bicep will help assist in any other pulling exercise. Don't be surprised if, once they start growing, you notice pull-ups and bent-over rows are getting more accessible too.
3. Concentration curls improve your mind-muscle connection:
You can apply this concept to any other muscle in your body. There may not be a specific movement like this, but working on tension and feeling the muscle for maximum growth can be used with every exercise.
Concentration Curls: Add It To Your Arm Workout
Now that you have finished learning about the standard concentration curl, you should fully understand the function of the biceps, how this exercise is the king for feeling it work and grow, and how to perform it correctly. If you want to take your arm goals one step further, add in some dumbbell forearm exercises for even more impressive-looking guns. Throw these into your next arm day, and after a few weeks, you'll be posing in every mirror you walk past.
Related:
Prepare to maximize your gains with our exclusive 12-week hypertrophy training program. Choose between a 4 or 5 day training split and gain 2-12 pounds of muscle over 90 days...
References:
- “ACE - ProSourceTM: August 2014 - ACE Study Reveals Best Biceps Exercises.” Www.acefitness.org, www.acefitness.org/continuing-education/prosource/august-2014/4933/ace-study-reveals-best-biceps-exercises/. Accessed 3 Aug. 2022.
Travis Halena
Author