Axle Bar & Fat Bar Training

Fat bars, thick bars and axle bars develop levels of muscle and strength that standard equipment can't match. It's not uncommon for even an experienced lifter to make significant muscle gains in just a few months by switching to thick bar training.

What Is Thick Bar Training?

Thick bar training has been around for decades. Old-time strongmen used it to develop levels of size and strength that are hard to comprehend today.

Thick bars (also called fat bars) are simply barbells, dumbbells and pull-up bars with a thicker handle. Standard equipment usually has a 1 inch thick handle. Thick bars usually have handles between 1.75 and 2.75 inches thick.

Thick bar training began because, in the old days, there was no real strength equipment available, so lifters improvised with railway and truck axles as barbells. That's where the axle bar gets its name.

Thick bar training simply means using a thick barbell, thick dumbbells and a thick pull-up bar in your usual training program.

For a long time, thick bar training was used mostly by elite soldiers, pro athletes and champion bodybuilders, because they knew how effective it was and could afford the specialty equipment. A single axle bar typically costs over $200, and a full set of thick-handled barbells, dumbbells and pull-up bars costs far more.

It's quite amazing that something as simple as switching to a thick bar can unlock such major muscle and strength gains, not just in the hands and forearms but throughout the whole body. Any skepticism usually disappears the first time you use a thick bar. In fact, you may want to take it easy the first time: many lifters report that their forearms and biceps are sore to the touch for days after their first thick bar workout.

Why Thick Bars Build More Muscle and Strength

There are several reasons thick bar training works so well.

Irradiation and Harder Muscle Contractions

Thicker handles stimulate far more muscle activation in the hands and forearms, and in the upper arms and whole upper body. This works by the principle of irradiation: when you contract a muscle hard, the muscles around it contract as well. So to get a maximal contraction in your biceps, for example, you need your forearms contracting maximally too. More muscle activation means significantly bigger muscle and strength gains.

Weak Links (and "Neural Inhibition") Eliminated

Your body is highly sophisticated. It has built-in protective mechanisms to minimize the risk of imbalance and injury, so it will "hold back" the strength and size of some muscles if it detects that the muscles around them are too weak. This is known as "neural inhibition."

This is one reason successful powerlifters work hard to build huge, powerful back muscles to improve their bench press. It sounds counter-intuitive at first, but training your "pulling" muscles makes you stronger on your "pushing" muscles, because your body needs that balance and stability to get stronger.

Your hands are the point of contact with the weight in almost every exercise, but most lifters greatly underestimate the role the hands play in getting stronger and bigger. Thick bars make your hands, fingers and forearms so much stronger that your body can finally stop "holding back" the muscle and strength gains in your upper arms, back and chest.

Training at All Angles, Automatically

Thick bar training automatically trains your hands, fingers and forearms at all angles. If you are bench pressing, the thick bar trains your hands and forearms in a completely different way than if you are doing chin-ups on a thick bar. Other grip training methods, like grippers, can be useful too, but they are one-dimensional: they train the hands and forearms the same way over and over, which can lead to imbalances and injury.

Thick bars also replicate the natural function of the human hand: lifting heavy, awkward objects. Humans evolved to use their hands to climb trees and rock faces and to carry logs and animals. Thick bars are a great way of replicating this.

Your Body Is Only as Strong as Its Weakest Link

If your back and legs can deadlift 700 lbs but your hands can only hold 300 lbs, your deadlift is 300 lbs. By strengthening your hands, wrists, forearms and upper arms with thick bars, you can make your whole body stronger.

Less Stress on Joints, Fewer Injuries and Imbalances

Many people start thick bar training because of how fast it adds muscle compared to a standard bar, but many lifters also report that it has helped with all types of injuries, including wrist, elbow and shoulder issues. Thick bars seem to shift stress off the joints and onto the muscles, which is exactly what we want.

This is thought to be because a thick bar spreads the weight over a larger area of the hand (just imagine bench pressing with a thick bar), so the weight is more evenly distributed through the entire arm. It's a bit like the difference between someone standing on you in sneakers and someone standing on you in high heels.

A thick bar also changes the biomechanics of the lift, so the forearm extensors (the muscles on the top of the forearm) and the forearm flexors (the muscles on the bottom) work in similar amounts. Pick up a thick-handled dumbbell and you'll feel it instantly. With standard bars, the forearm flexors do almost all the work, which can cause imbalances, injuries, strength plateaus and tendonitis. Fewer injuries also mean more productive training, because consistency is essential.

How to Add Thick Bar Training to Your Workouts

To add thick bar training to your program, simply use thick bars for everything: barbells, dumbbells and pull-up bars, on all exercises. That includes bench presses, overhead presses, chin-ups, pull-ups, rows, deadlifts, curls and triceps extensions. For a simple plan to get started, see the Quick Start Arm Size Training Guide.

A note of caution: take extra care when you begin thick bar training and drop the weight at first. You may not be able to handle your usual weights right away, but don't worry: your hands and forearms will quickly catch up, and you'll blow your old max lifts out of the water.

Axle Bar vs Fat Gripz

An axle bar gives you thick bar training on barbell lifts. Fat Gripz give you thick bar training on almost everything you already use.

Not sure which size to start with? The Fat Gripz Pro (2.25 inches) is the best size for most people. If you have smaller hands or a weaker grip, start with the Fat Gripz One (1.75 inches). Advanced lifters can step up to the Fat Gripz Extreme (2.75 inches).

Why We Created Fat Gripz

We created Fat Gripz when we learned how many pro athletes and bodybuilders had used thick bars to develop massive arm size and strength, and then saw how well they worked when we tested them ourselves. Unfortunately, thick bars and thick-handled dumbbells are rare and expensive, so we created Fat Gripz to make thick bar training available and affordable to everyone.

We're very proud that Fat Gripz are highly regarded in the strength community and used extensively by the military (including the U.S. Special Forces Expeditionary Warfare Group and the British Royal Marine Commandos), champion bodybuilders (including two Mr. Olympias, Jay Cutler and Phil Heath), professional football, baseball, and basketball teams, and athletes across many physique and strength sports.

Thick Bar and Axle Bar FAQs

What is an axle bar?

An axle bar is a thick, smooth barbell, usually about 2 inches in diameter, used mainly in strongman training. The name comes from old-time strongmen who lifted railway and truck axles. Because the handle is so thick, it trains your grip, forearms and arms much harder than a standard barbell.

How thick is an axle bar?

Most axle bars are between 1.9 and 2 inches thick, about twice the diameter of a standard 1 inch handle. Fat Gripz come in three thicknesses: 1.75 inches (Fat Gripz One), 2.25 inches (Fat Gripz Pro) and 2.75 inches (Fat Gripz Extreme).

What is a fat bar?

Fat bar is another name for a thick bar: any barbell, dumbbell or pull-up bar with a thicker handle than standard equipment. Fat bars usually have handles between 1.75 and 2.75 inches thick. An axle bar is one type of fat bar.

Can Fat Gripz replace an axle bar?

For building grip strength, forearms and arm size, yes. Fat Gripz turn any barbell, dumbbell, pull-up bar or cable handle into a thick bar, so you get thick bar training on every exercise instead of only barbell lifts. If you compete in strongman, also practice your axle events on a real axle bar, because the bar's length, weight and balance are part of the event.

Which Fat Gripz size is closest to an axle bar?

A standard axle bar is about 2 inches thick, between the Fat Gripz One (1.75 inches) and the Fat Gripz Pro (2.25 inches). The Pro is the best size for most people. If you have smaller hands or a weaker grip, start with the One, then move up as your grip gets stronger.

Have more questions? See our full Fat Gripz FAQs.

Conclusion

Fat Gripz and thick bars develop levels of muscle and strength that standard equipment can't match. It's not uncommon for even an experienced lifter to make significant muscle gains in just a few months by switching to thick bars. Get some Fat Gripz and unlock major muscle and strength gains.