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Any weight lifter with some experience would agree that variation is a fundamental part of muscle growth. We talk about gym routines, but doing the same thing over and over again is not always a good idea for your progression. Instead, you want to challenge your muscles and make them recruit new fibers every time. Have you thought about fat grip training for a change?

In this article, we’re reviewing the rationale and scientific literature about thick bar training. Fat grip training is lifting weights with thick handles or attaching cylindrical thick grips - usually made of rubber - over barbells and dumbbells to increase the difficulty. Training with dumbbell grips or barbell grips is not only more challenging than the traditional Olympic bar, it is also an excellent aid to strengthen your grip and recruit more muscle fibers with the same exercise.


Fat grips are designed to mimic thick bars or axle bars. They have a larger circumference as compared to the curl bar or Olympic bar. Thus, they are designed to strengthen your grip and forearms as you do push or pull exercises.

You have different designs, but it is generally recommended to have a bigger grip area and smaller ends. You should keep in mind the diameter of the plates and that of the thick bar to avoid any sliding or loose weights on the sides (1).

One of the flaws in thick bar design is that the manufacturers do nothing to facilitate its maneuverability. Most of us are not used to thick bars, and a simple design consisting of just a thick cylinder can be hard to use.

That’s why we’re brought to the market a unique thick bar adapter with wing-shaped palm support that solves a few problems encountered by thick bar users. The ergonomically designed wing provides excellent palm support while distributing pressure evenly. This minimizes strain on your hand and wrist, allowing you to train longer and more comfortably. The winged handle stimulates the forearm allowing for better arm and chest activation due to muscle irradiation.

We call them Optimo Pro grips, and you can purchase them HERE.

Meanwhile, let’s review why some athletes and weightlifters are looking for thick bars instead of the traditional Olympic bar.


Weightlifters and many athletes can find extra benefit in training with a thick bar. Here’s a top 5 of excellent reasons to try them:

  1. You will improve grip and forearm strength: A thick bar will be useful to activate more muscle fibers on your forearm. Your grip will strengthen as your forearms become stimulated.
  2. Your joints will stay more protected: As your grip and forearms strengthen, they will also protect your articulations. Elbow pain and tendinitis symptoms may reduce after using a thick grip.
  3. Your technique will keep on improving: After a while, the combination of a firmer grip and a thick bar will enhance your stance and technique. It will be easier to keep your articulations aligned, and you’ll have a highly transferable upper body strength.
  4. Improved weight distribution: With a thick bar, the weight is more evenly distributed. Your body becomes more aligned to support the extra weight of the bar. Thus, there is no overcompensation to one side or the other. This reduces your chances of injury when your technique is symmetrical.
  5. Stronger neuromuscular response: The neuromuscular space is where the nerve sends signals to the muscle. A thick grip stimulates the neuromuscular junction and makes your muscles more responsive when you need them. This is particularly the case in your forearm muscles.

But why would you need forearm strength, arm strength, or a tighter grip?

First of all, many of us forget about forearm training in the upper body routine. Wouldn’t it be great to stimulate this muscle while completing a row or a deadlift?

Secondly, if you’re an athlete, hand strength can be advantageous. For example (1):

  • A football player would improve his catching and ball carrying. He would also enhance pass protection.
  • A basketball player will also improve his catching and ball control. Dribbles and passing are both easier if you have stronger forearms.
  • Wrestling athletes would grasp, pull, and have better wrist and hand control during a fight.
  • Baseball players need hand strength and joint protection for wrist rolling and swinging.

However, be prepared to feel different throughout the workout. It might be initially a bit difficult to hold your grip, and you may need to use a lighter weight. To make it easier for you, we have developed a useful support wing on our Optimo Pro grips.


Thick bar training is an exciting approach, but how does it work? Here’s a technical explanation made simple:

We all know that bar thickness and texture are fundamental to maximize the grip. To hold tightly on a bar, you need to activate the forearm flexors and extensors. But their work during free weight training is highly undervalued. Thick bars are an excellent tool to strengthen the grip by achieving a more profound activation of these muscles.

For every repetition, you go through a positive phase where you lift the weight and a negative phase where you go back to the starting position. With a regular bar, you’ll be activating the flexors and extensors of the forearm in the negative phase, as the muscles keep the weight under control against gravity. But depending on the exercise and your technique, you may not be activating them at all.

With a thick bar, muscle fiber recruitment during the negative phase is more thorough. You may also feel the work done on your forearms on the positive phase of the repetition. In other words, you’ll engage in more muscle activation, with no relaxation or rest during negative movements. This recruitment is maximized during curling or pulling exercises, where you’re holding the bar against gravity (1).

Besides muscle recruitment, you may have heard about neuromuscular activation or neural drive. It is basically promoting stronger contractions by stimulating the connection between nerves and muscles.

When you’re starting to work out, neuromuscular activation is usually done by increasing the number of repetitions. More repetition equals more constant stimulus and strengthening of this neuron-muscle communication. With a thick bar, there is continuous activation and neuromuscular stimulation without as many repetitions. As a result, the connection becomes more responsive, and you will develop power strength and faster muscle response (2).

In considering all of this, we also have a recommendation for you:

To take the best out of a thick bar, think about your grip. Is your grip essential for completing the exercise? If you do a seated machine chest press, you don’t even need to close your grip. It is not critical to the movement. In a bench press, you can also hold the weight with minimal grip.

In contrast, holding on to the bar tightly is essential in deadlifts, biceps curls, and horizontal rows. Otherwise, the bar would slip through your fingers. That’s why some researchers suggest considering pulling exercises if you’re after hand and forearm strength (3).


A solid rationale is a great starting point, but it should always be confirmed with human trials. Research on sports medicine and biomechanics supports the use of thick bars in different settings.

In weightlifting, we have a classic study published in the International Journal of Industrial Ergonomics. The investigators evaluated three bar diameters and how the participants’ muscles worked throughout the activity. They found that a smaller handle caused a higher voluntary muscle contraction. But neuromuscular activation was very low. With a larger diameter, the exercise elicited greater neuromuscular response as measured by electromyography. The results are even more exciting because they were untrained individuals, so just imagine what a thick bar can do for you as a trained weightlifter (2).

Another interesting study was performed on males with weightlifting experience. It was published in the Journal of Strength and Conditioning Research. The study evaluated 3 bar diameters and 6 exercises, providing interesting information about thick bar training. We can break it down like this (4):

  • Participants had to reduce the weight as bar thickness increased: Participants used a greater weight in Olympic bars in almost every exercise. But then, they had to reduce the weight to complete the same exercise with a thicker bar. This effect was particularly marked in the deadlift, with a 55% reduction of weight to maintain a good technique. This shows that thick bars increase muscle activation in areas we usually do not work, making the exercise more challenging.
  • Time to exhaustion in grip endurance test was reduced as thickness increased: In other words, grip endurance was lower using a thick bar. You could say that this type of handle works similar to increasing the load in a weight machine. It recruits more muscle fibers, exhausting them and reducing your endurance. This is actually good for forearm workouts.
  • Participants reported greater forearm DOMS with a thick bar: You usually know that your muscle was adequately trained when it feels numb or hurts the day after. This is delayed-onset muscle soreness or DOMS. You can experience DOMS when you change your routine, for example. It’s a new challenge, and DOMS can be a reliable marker of doing a good job. Well, participants of this study reported greater forearm DOMS when using a very thick bar. This is a sign of muscle activation. It is also a sign of a new type of stimulus for their muscles. That’s precisely what you need to keep challenging your body.
  • Pushing exercises were more comfortable with a thick bar: These researchers found no significant difference in 1-Rep Max during the bench press. But they also had this hypothesis that it would feel uncomfortable. But participants reported the opposite. They said it was more comfortable to lift the bar and mentioned no pressure increase or discomfort in their grip.


There is no routine done exclusively with a thick bar. Actually, that wouldn’t be practical because we want to keep challenging the muscles with different variations every time. However, we do encourage using a thick bar whenever possible to strengthen your grip, engage your forearms, and maximize your push and pull exercises.

You can try with preacher curls, standing curls, French curls, an upright row, or an inclined bench press. They will all feel different after trying a thick bar, and you’ll know it’s working. The day after, delay-onset muscle soreness will let you know that you worked it out.

If you’re decided to give it a try, remember the learning curve we need to go through when using new equipment. You may initially find it difficult to hold onto the bar. So, we recommend reducing your weights and getting used to it before powering up. Also, keep a partner around if you feel unsure or if you’re trying something new (1).

To make it easier for you, our team has developed a new type of thick grip. It is not a simple cylinder, like others you’ll find elsewhere. This ergonomic gym grip has a particular support wing designed to give you more stability and facilitate the exercise. The learning curve won’t be as harsh, and you’ll have the same gains on your forearms.

We call them Optimo Pro grips, and it is now made available for purchase  HERE.



  1. Channell, S. (1990). Equipment utilization: The fat bar. Strength & Conditioning Journal, 12(4), 26-27.
  2. Grant, K. A., Habes, D. J., & Steward, L. L. (1992). An analysis of handle designs for reducing manual effort: the influence of grip diameter. International Journal of Industrial Ergonomics, 10(3), 199-206.
  3. Fioranelli, D., & Lee, C. M. (2008). The influence of bar diameter on neuromuscular strength and activation: inferences from an isometric unilateral bench press. The Journal of Strength & Conditioning Research, 22(3), 661-666.
  4. Ratamess, N. A., Faigenbaum, A. D., Mangine, G. T., Hoffman, J. R., & Kang, J. (2007). Acute muscular strength assessment using free weight bars of different thickness. Journal of strength and conditioning research, 21(1), 240.