How Improving Grip Strength Can Help You Increase Overall Muscle Mass

“My experience has shown me that taking the time and energy to directly stimulate the forearm musculature leads to increased ability to handle heavy weights in many exercises.”

– Dr Ken Leistner, The Steel Tip1

Some lifters focus on grip training with grip strength as the end main goal. For example, some focus almost exclusively on closing the different versions of the Captains of Crush Grippers or on setting a new personal best using the Rolling Thunder.

Athletes, if they desire grip strength at all, do so to become better at their sports. Among the greatest examples of athletes with phenomenal grip strength are mountain climbers. Even average mountain climbers can often be seen performing one-finger pull-ups!

Bodybuilders should take an interest in grip strength for two reasons. The most obvious is that the size of the muscles we use for grip strength make up the size of the forearm, which ideally should be in proportion to the rest of the body.2

The second reason that you should take an interest in grip strength is that increased grip strength can help you lift more weight, and thus a stronger grip helps you create a stronger mass-building effect from your workouts. Here is how increased grip strength can help you lift more weight in exercises such as deadlifts or rows.

During deadlifts, your leg and back muscles have a certain pulling strength – for example, 300 pounds. But if your hands can hold only 200 pounds, the nervous system won’t allow full activation of the legs and back because, consequently, the bar will fall out of your hands. The result of this is understimulation of the leg and back muscles. This issue is bigger in rows and deadlifts, but less important in other exercises such as presses and squats.

Lifting straps might, to some extent, remedy this problem by providing some of the grip strength. Yet, relying exclusively on straps might not be the best overall solution.


How Can I Develop Grip Strength?

Now that we’ve realized the benefit of grip strength in building whole-body strength and size, it’s natural to ask how we can develop grip strength most effectively.

To develop grip strength, you can take two basic approaches:

  1. Train the grip directly with an exercise that isolates the movement to the hand and/or forearm.

Pros: Greater opportunity to direct mental focus to the grip muscles, which may increase muscle activation.3</>

Cons: Inefficient as far as stimulating large amounts of muscle. 

  1. Use a modified version of a multi-joint exercise that places special stress on the muscles of the hand and/or forearm.

Pros: Great efficiency as far as stimulating grip strength and other muscles with one exercise.

Cons: Less opportunity to focus on the grip during the exercise.

Depending on the structure of your program, it’s recommended to use one or more modified multi-joint exercise plus one or more isolation exercise in order to fully develop the grip.4

Because of the need to perform a multitude of tasks, the hand and forearm is a very versatile structure, consisting of 16 muscles in the forearm and 10 muscles in the hand.5 The three main joints to consider are the humeroulnar joint (the joint that allows the forearm to rotate along its long axis), the wrist joint and the fingers, each finger having two or three joints.

There are nine main movements to consider, with several subgroups of movements for the fingers.

Humeroulnar joint (the joint that allows the forearm to rotate around the long axis)

  • Supination
  • Pronation

The radiocarpal joint (the wrist joint)

  • Flexion (palm of the hand moving towards the inside of the forearm)
  • Extension (backside of the hand moving towards the backside of the forearm)
  • Radial flexion (the thumb side is moving towards the side of the forearm)
  • Ulnar flexion (the pinky side is moving towards the side of the forearm)


  • Flexion (emphasizing distal joints)
  • Extension
  • Opposition (moving the thumb towards the other four fingers)
  • Opposition is often trained with the so-called pinch grip, which combines opposition of the thumb with flexion of the proximal joint of the other four fingers.6

If your focus is forearm size, then generally speaking, you should include all of the above listed movements in your training program either with an isolation exercise or a modified multi-joint exercise that places extra stress on the forearms and hands.

However, as with any other form of training, grip training is highly specific to the task. Strongman Mike Bruce trains the partial deadlift and manages 1,500 pounds, but never trains with grippers and cannot close the No. 3 Captains of Crush Gripper,7 which supposedly requires 280 pounds to close.8

Because of the implications for overall muscle mass development, the rest of the article will focus on developing the grip strength needed to use heavier loads in your barbell, dumbbell and cable training.


Developing a power grip

According to the textbooks, the type of grip used to grab a barbell (or dumbbell) involves a so-called power grip, which places all fingers and the thumb around an object.9

Research indicates that grip strength can be the limiting factor for performance in pulling types of exercises such as deadlifts and rows, but not in pressing types of movement.10 Thus, the given examples focus on pulling-type exercises.

Thick bar training has historically been used extensively to develop grip strength – famously, by British strongman and educator Thomas Inch a century ago. Today, thick bar training still has many proponents, such as esteemed strength coach Charles Poliquin.11

A normal-sized Olympic bar is about 1.1 inch in diameter, while a “thick bar” might be two to three inches in diameter. If your gym doesn’t have an actual thick bar, you can, for a moderate investment, acquire the two to three inches of thickness with so-called thick bar sleeves (see, or

Those who are used to lifting normal-sized bars or dumbbells and then experiment with thick bar training (two to three inches in diameter) will notice that – at least right there and then – they will have to reduce the load. Thus, from an immediate standpoint, using thick bars doesn’t seem to be a good proposition. Although training with a thick bar clearly will make you stronger with a thick bar after a while, you might still end up using less load in your deadlift than you would have used with a thin bar.

Thus, even though thick bar training might improve your grip strength, it’s not a great idea to begin training with thick bars only.

The question we are focusing on is this: How should I incorporate thick bar training into my routine to help me use more load in other exercises?

Let us take a look at how thick bar training really works.

All muscles in the body are subject to the so-called length-tension relationship, which shows that a given muscle is relatively weak in a shortened position, has its greatest strength at an intermediary length and loses strength again when placed in an elongated position.12 In line with the fundamental length-tension relationship, research shows that maximal handgrip force occurs at an intermediate grip span.13

When you close your hand, the muscles that flex the fingers get shorter (approaching the weaker range). As you open your hand, the muscles that flex the fingers approach that “intermediary” grip span. In a fully open hand, or with the fingers only slightly flexed, the muscles that flex the fingers are at their weakest range.

Because of different hand sizes among lifters/bodybuilders, it isn’t possible to give a general recommendation for which bar diameter is the optimal intermediary range.

Many researchers have studied muscle activation patterns during minor variations of the same exercises and found that the muscle activation pattern is highly specific to the specific variation of an exercise.14 This fact is expressed in the concept of functional differentiation.

According to the concept of functional differentiation, the nervous system fine-tunes activation of motor units according to the optimal line of pull for a given exercise. Functional differentiation within skeletal muscle refers to the ability of the central nervous system (CNS) to control, with a degree of independence, individual subunits of a muscle during a particular muscle contraction. Essentially, the concept of functional differentiation within skeletal muscle suggests an ability of the CNS to selectively activate those segments of a muscle that have the most appropriate line of action for the task as a means of ensuring the muscles’ efficient utilization.15

Thus, based on the principle of specificity and the principle of functional differentiation, we can fairly assume that if we perform a certain exercise with three different grips – for example, grips that are one, two and three inches in diameter – that challenge the fingers to contract at different lengths, we are stimulating the finger flexors differently.

From the point of view of training the same muscle at different lengths, it’s also fair to say that training at a short, intermediary and long length results in a complete stimulation of that muscle group. Challenging a given muscle group at its short, intermediary and long length is the physiology behind the “position of flexion system,” which is valid and highly useful for all exercises.16

There are several mechanisms through which training with a larger bar diameter could transfer to training with a smaller bar diameter.

Transfer mechanism #1: Increased focus on the grip.

During deadlifts and pulls with thicker bars, there is often a feeling that the bar is falling out of the hands. This feeling may translate into increased focus on the grip and thus a stronger contraction.3 Through this mechanism, you aren’t getting “new strength”; you’re using more of the strength that you already have.

Transfer mechanism #2: Irradiation.

Irradiation is defined as the “spread of muscle activity to other muscles besides those primarily responsible for the task.”17 Irradiation may happen during high-effort contractions.

A larger bar diameter forces you to contract your finger flexors harder (see explanation below), even though the external load is the same. Thus, a larger bar diameter may create irradiation, primarily to the entire forearm. Irradiation to the forearm might be a key reason that some lifters find that thick bar training increases forearm size in general.

During pulling-type exercises, we flex our fingers around the bar to maintain the grip. Our fingers must counteract the effects of gravity that work on the bar and tend to open the hand. Technically speaking, gravity is creating an extension torque around the different joints of the hand.

The torque is determined by the load on the bar multiplied by the lever arm, which is the horizontal distance from the centre of the bar or dumbbell to the proximal (first) joint of the fingers.

The picture below shows a power grip on the end of a regular Olympic bar. The bar is thicker than a regular bar, but not super-thick. Notice the center of the bar and imagine a plumb line extending from the centre of the bar and towards the floor. Notice the distance from the first joint of the finger to the plumb line. Also, notice that this plumb line falls to the right of the second joint of the finger.

The distances between the plumb line and the first and the second finger joints means that the bar creates and torques around these joints, a torque that tends to open the hand.

You can easily imagine how the lever arms (the horizontal distances from the centre of the bar to the first and second joint of the fingers) are shorter with a thinner bar.

Thus, even though the load is the same, the torque around the joints is smaller with a regular bar than a thick bar. Therefore, it requires less strength of the fingers to maintain the grip.

In conclusion, the fact that the larger bar diameter forces the lifter to contract the finger flexors harder for the same load could cause a spread of the muscle contraction (irradiation) to the entire forearm.

Transfer mechanism #3: Post-tetanic potentiation

Your muscles’ ability to produce force is extremely variable and depends upon the “activation history” of the muscle. For example, is your muscles’ ability to produce force enhanced after a brief maximal contraction of five to 10 seconds? This phenomenon is called post-tetanic potentiation.18

Some coaches attempt to take advantage of post-tetanic potentiation of the finger flexors by alternating sets with a larger bar diameter with sets of smaller diameter.19

Transfer mechanism #4: Joint-angle carryover

During thick bar training, the finger flexors are contracting isometrically. Strength gains from isometric training are generally specific to the joint angle trained, but with some carryover to other joint angles “around” the trained angle. The carryover is smaller if the isometric training has been performed with the target muscle in the shortened position. The carryover is explained via neurological mechanisms.20

Thus, it’s possible that training with a larger bar diameter transfers better to training with a smaller bar diameter than training with a smaller bar diameter would transfer to strength with a larger diameter.

Now that we understand how thick bar training might help increase the load you can lift with a smaller bar diameter, let’s look at some specific training strategies.

The strategies are mostly relevant in deadlifts, rows, pulls as well as dumbbell exercises where the handle is vertical in portions of the movement. Examples of dumbbell exercises where the handle is vertical include hammer curls and certain types of overhead triceps extensions.

Staying in line with the physiology of the length tension relationship, all the strategies revolve around using three different bar diameters. Although the best solution would be to get actual thick bars, the most cost-effective solution is to invest in thick bar sleeves.

The best solution that we’re aware of is to invest in Fat Gripz Original (2.2-inch thickness) and Fat Gripz Extreme (three-inch thickness). With the two versions of Fat Gripz and your normal handles, you have access to the three different grip widths discussed above. (See

For flexibility and application, the examples do not refer to any particular split. However, to see improvements, there should be some kind of thick bar training at least twice per week.


Thick Bar Training Strategies

Strategy #1: Using different bar diameters from exercise to exercise and/or day to day

Choose two exercises for each movement pattern (for example, conventional style deadlifts and semi-sumo deadlifts). Use a normal bar diameter for the exercise in which you can handle the most load. Alternate the two thicker bar diameters every other workout. Train each exercise with whatever set/rep combination you would normally use.

Focus on the grip during the exercises in which you are using the thicker bar diameter.

Use one of the thicker bar diameter during your warm-up sets on the day that you train with the thinner bar diameter (to take advantage of post-tetanic potentiation).

Strategy #2: Using different bar diameters from set to set for the same exercise

Strategy # 2 explicitly aims to take advantage of the post-tetanic potentiation by alternating a set of short, maximal effort with a set of medium to high reps. The strategy is the easiest to execute with an exercise in which the load can readily be adjusted (for example, heavy dumbbell rows or cable exercises). However, it will be worth your efforts to also use it for deadlifts!

Use strategy #2 twice per week. On Day 1, use the two-inch diameter grip, and on Day 2, use the three-inch diameter grip.

The first day you use this exercise is a test. Your goal is to find (1) A load that you can hold for five seconds using the three-inch grip, (2) a load that you can hold for five seconds using the two-inch grip, and (3) a load that you can perform six repetitions with using a normal grip.

On subsequent sessions, you alternate holds of five to 10 seconds immediately followed with a set of six to 10 repetitions. When you can hold the load for 10 seconds, then that load is increased. When you can perform 10 repetitions, then that load is increased. Repeat four to six times per exercise.

Strategy #3: Using different bar diameters within the same set.

Strategy #3 is designed to be used with high-rep sets in the 15 to 20 brackets. You will use the load that you would normally use. You begin the set with the thickest thick bar sleeve and perform as many repetitions as possible with that sleeve (for example, seven). Then, taking only the rest needed to change the sleeves to the second thickest sleeve, continue and perform as many repetitions as possible with that sleeve. If there are still repetitions left, finish the set without any thick bar sleeve on the bar.

Wrapping It Up

This article discussed the physiology of thick bar training and gave three practical examples of how to apply thick bar training to your routine. Thick bar training will make your finger flexors very strong. Thus, to maintain muscle balance, you should also train your finger extensors.

Here’s a simple yet effective way to train your finger extensors. Assume a push-up position, ready to perform push-ups on your fists. However, straighten your fingers so there is a 90 degree angle between your fingers and your hand. Depending on how you place your body, you can put more or less pressure on your fingers. Start with a position that you can hold for 20 seconds, and focus on pushing the back of your fingers into the floor. When you reach 45 seconds, change your position to place greater load on your hands. Perform two to four sets at the end of each workout in which you have trained with thick bars.


  1. Leistner KE. The Steel Tip. 1985;1(2).
  2. Fitness Calculators. Truly Available at: Accessed February 5, 2013.
  3. Snyder BJ, Fry WR. Effect of verbal instruction on muscle activity during bench press exercise. J Strength Cond Res. ;26(9):2394-2400.
  4. Jensen K. First improve the weak link, and then improve the function of the entire kinetic chain. In: The Flexible Periodization Method. Mississauga, ON: The Write Fit. 2010:59.
  5. Andreasen E, Bojsen-Moeller F. Bevaægeapparatet Anatomi I. (The anatomy of the motion apparatus/system.) Copenhagen: Gyldendal. 1990:224. (In Danish.)
  6. Jensen, K. Dynamic pinch grip training. Available at: Accessed February 5, 2013.
  7. Personal communication with Mike Bruce.
  8. Captains of Crush® Grippers. Available at: Accessed February 5, 2013.
  9. Enoka RM. Voluntary movement. In: Neuromechanics of Human Movement. 4th ed. Champaign, IL: Human Kinetics. 2008:298.
  10. Ratamess NA, Feigenbaum AD, Mangine GT, Hoffmann JR, Kang J. Acute muscular strength assessment using free weight bars of different thickness. J Strength Cond Res. ;21(1):240-244.
  11. Poliquin C. Getting into the thick of training. Available at: Accessed February 5, 2013.
  12. Chandler TJ, Brown LE. Biomechanics of human movement. In: Conditioning for Strength and Human Performance. 2nd ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. 2013:90.
  13. Fioranelli D, Lee M. The influence of bar diameter on neuromuscular strength and activation: inferences from an isometric unilateral bench press. J Strength Cond Res. ;22(3):661-666.
  14. Sale DG. Neural adaptations to strength training. In: Strength and Power in Sport. Oxford [etc.]: Blackwell Scientific Publications; 1992:250.
  15. Paton ME, Brown JM. Functional differentiation within latissimus dorsi. Electromyogr Clin Neurophysiol. 1995 Aug-Sep;35(5):301-9.
  16. Positions of flexion by Steve Holman. Available at: Accessed February 5, 2013.
  17. Enoka RM. Acute Adjustments. In: Neuromechanics of Human Movement. 4th ed. Champaign, IL: Human Kinetics. 2008:347