Does grip training increase forearm size?
Pure grip training is not the most effective way to stimulate forearm growth because it focuses on the finger flexors (flexor digitorum profundus and flexor digitorum superficialis).
Maximal forearm hypertrophy requires wrist work over a full range of motion.
In addition, grip training is heavily dependent on tendon strength and the efficiency of the central nervous system.
While there are many benefits to developing tendon strength and CNS power, forearm hypertrophy requires a different tactic – high reps and a multitude of exercises targeting all forearm muscles with the necessary intensity and movement amplitude.
Wrist Flexors & Finger Flexors
The finger flexors are the muscles that pull the fingers into a fist.
The wrist flexors pull the palm closer to the elbow (wrist flexion).
The finger flexors are engaged during wrist flexion, but the wrist flexors do not participate in finger flexion because their insertions end at the wrist.
To understand the idea a little better, you can try the following exercise:
Step 1: Make a fist.
Your forearm will bulge a little.
Step 2: Flex/clench your wrist.
Your forearm will bulge substantially more.
Here’s what’s happening. The first step activates only the finger flexors whereas the second wakes up the wrist flexors and the finger flexors.
| Wrist Flexors | Finger Flexors |
| Flexor Digitorum Superficialis | Flexor Digitorum Profundus |
| Flexor Digitorum Profundus 4 Heads | Flexor Digitorum Superficialis |
| Flexor Carpi Radialis | |
| Flexor Carpi Ulnaris | |
| Palmaris Longus (absent in 14% of the population) | |
| Flexor Pollicis Longus |
As you can see in the tables above, wrist flexion is dependent on a total of 5-6 muscles whereas finger flexion wakes up only two.
Conclusion
Complete hypertrophy of the forearm flexors requires wrist flexion and cannot be achieved solely through finger flexion.
Subsequently, exercises like pull-ups and deadlifts are actually inferior movements for that particular purpose.
A better choice would be to do wrist curls, wrist rolling and barbell finger rolls with wrist flexion.
Somewhat ironically, for the very same reason, wrist training is an inferior way to build grip strength as it does little to condition the finger tendons and the CNS. If you want to get a better grip, wrist curls are not on top of the list.
A Note on the Palmaris Longus
The muscle known as Palmaris Longus is considered an “evolutionary leftover” that flexes the wrist and tightens the palmar aponeurosis. Experts consider it a weak wrist flexor that doesn’t provide substantial flexing power. 14% of the population doesn’t even have that muscle. Some people have it on one arm but don’t on the other.
When the palmaris longus is absent, the other wrist flexors and the palmaris previs compensate.
Wrist Extensors & Finger Extensors
| Wrist Extensors | Finger Extensors |
| Extensor Carpi Radialis Longus | Extensor Digitorum |
| Extensor Carpi Radialis Brevis | Extensor Digit Minimi |
| Extensor Digitorum | Extensor Indicis |
| Extensor Digiti Minimi | Extensor Pollicis Brevis |
| Extensor Carpi Ulnaris | |
| Abductor Pollicis Longus | |
| Extensor Pollicis Brevis | |
| Extensor Pollicis Longus | |
| Extensor Indicis |
The finger extensors open the palm whereas the wrist extensors bring the outer part of the hand towards the elbow (wrist extension).
Optimal development of all extensors requires “wrist work”. Finger exercises (e.g., fingers extensions against a band) will not be enough as they don’t target all wrist extensors.
Recommended exercises: Reverse curls, hammers curls, reverse wrist curls, wrist roller.
Forearm Pronators and Supinators
A complete forearm workout includes forearm supination and pronation.
Supination = rotating your forearm until the palm faces up
Pronation = rotating the forearm until the palm faces down.
The muscles that supinate the forearm are the supinator, the biceps and the brachioradialis.
The muscles that pronate the forearm are pronator teres, pronator quadratus and the brachioradialis.
Out of all pronator and supinator muscles, the brachioradialis has the biggest impact on forearm size.
Recommended exercises:
- pronation and supination against a resistance band or with an objected weighted on one end;
- reverse curls to target the brachioradialis which works as an elbow flexor too;
Frequently Asked Questions
Do hand grippers increase forearm size?
Hand grippers build “crushing grip strength”, but they are one of the least productive methods for increasing forearm size because the wrist doesn’t move much, and only the finger flexors are under fire.
When forearm hypertrophy is the goal, wrist curls, barbell finger rolls with wrist flexion at the end and wrist rollers produce better results.
Will farmer walks increase the size of my forearm?
Farmer walks are a supporting grip exercise. Similar movements are not optimal for forearm hypertrophy by themselves because they work mainly the finger flexors and lack a concentric (positive) and an eccentric (negative) phase.
I am a beginner. Should I train my forearms directly?
If you are a total beginner (e.g., someone who can’t do a pull-up), you would be better off learning the basic movements before doing isolation work. At that point in your development, you wouldn’t benefit much from highly specialized forearm training.
However, after a couple of months, you may consider doing direct forearm work if you want to maximize the potential of your forearms.
Is direct forearm training really necessary? Aren’t basic exercises sufficient?
If you have good forearm genetics (long muscle bellies), then you may not need to target the forearms directly – general back and arm exercises would be enough.
But if your forearms are a lagging body part and/or you want to boost their growth as much as possible, direct work involving a lot of wrist flexion and extension is your best bet.
Don’t listen to 5×5 gurus saying that your forearms and biceps will grow from holding the bar during squats because they won’t.
How often should I work my forearms?
The forearm can handle a lot of punishment if you build up to it. But in general, more than 3 times a week would be too much for the average individual. Going beyond would get you really close to the point of diminishing returns.
Will forearm training thicken my wrists?
Your wrists will get stronger, but they won’t get much thicker as the joints are made of connective tissues and do not hypertrophy.
The tendons get denser over time but the process is incredibly slow (think years) and even then, the overall circumference of the wrist won’t increase much.
I have time only for 1-2 forearm exercises. What should they be?
Option 1:
- barbell finger rolls with wrist flexion
- reverse biceps curls
Option 2:
- Wrist rolling in both directions
Example Forearm Routines
1. No specialized equipment
The routine below is simple and skips some forearm movements, but it can be done in almost any gym and hits all major muscles contributing to overall forearm growth.
Barbell or dumbbell finger rolls with wrist flexion – 3×8-12
https://www.youtube.com/watch?v=86rSLJEWe3M
Hammer curls – 3×8-12
Reverse curls – 3×8-12
2. Specialized equipment
Barbell or dumbbell finger rolls with wrist flexion – 3×8-12
Towel hammer curls (you can loop a towel through a barbell plate for those) – 3×8-12
Wrist roller – 2-3 sets each side
If you are a forearm fanatic, add pronation and supination exercises with a sledgehammer for example.
It doesn’t matter if you do all the forearm exercises in the world because just like calves they 100% genetic.
Sure, you think they growing after some hardcore forearm workouts but 6 months later, measure them cold and they exactly the same size.
Thats sick placebo for you.
My father has big calves and forearms and all he does for them are walking and typing on a keyboard.
But I have height, which I would rather have. You can’t have everything.
Good article though. I wish forearms responded to training on ectomorphs but for a very high percentage of ectos (97% perhaps) negligible growth will occur.
Still give it a go if you knew to the game, but if after 6 – 12 months of direct forearm training you have less than 1 cm of growth, your effort is best spent on another body part. Same as calves.
That’s true. Long belly forearms look nice even without training.
The longer your forearm is, and the shorter the muscles are, the less effect training has as there’s little muscle to grow in the first place.
But forearm training has a great carryover to arm work too. A strong forearm will allow you to hit your upper arms harder.
Brett is flat-out correct.
In my experience, however, there is a noticeable difference between doing no direct work for forearms (and calves) and doing *some* direct work during the week. Point is that some is better than none and is useful for strength-transfer reasons.
I have never tried near-daily training for these bodyparts, so I don’t know if that matters, beyond creating temporary (acute) edema. Does it? The other fix, as some say, is eating yet more, which is a non-starter for other reasons.
Forearm and grip training for strength (which will improve) has many uses, however, including, as mentioned, carryover to most lifts. The trick in all this is volume-economy—knowing where and in what quantity to put in the effort and volumes.
I have poor forearms, and thick calves. They are pretty constant, even though I workout both of them regularly.
Brett isn’t entirely correct. Nobody is more ectomorphic than me, but with a lot of dedicated forearm work, I’ve built muscle. Of course, there are plenty of guys who never lift and have forearms much larger than mine. Such is life.
How do you train your forearms?
Seated forearm curls, seated reverse forearm curls, (both with arms supported on thighs), reverse curls, sometimes hammer curls. And a lot of mobility work, and a lot of time on the rowing machine. The rower isn’t heavy grip work, but it is hours per week of gripping even if it’s just the fingertips and not a tight, full- handed grip.