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Forearm Muscles, Bones and Anatomy

Your complete guide to the bones and muscles of the forearm.
Headshot of the Critical Body Personal Trainer Liam Brown
Written By Liam Brown
Last Updated on 19th March 2021
The anatomy of the forearm muscles
The forearm, which is sometimes referred to as the lower arm, is the region of the human body that lies between the elbow and the wrist. As you will see, however, many of the forearm muscles actually insert further down the upper limb into the hand because they’re responsible for flexing and extending the fingers.

The forearm muscles consist of flexors, which lie in the anterior compartment of the forearm, and the extensors, which lie in the posterior compartment [1]. The muscles of the forearm also consist of supinators, which turn the palm down, and pronators, which turn the palm up. Additionally, the brachioradialis is another forearm muscle, one which flexes the elbow.

Anatomically speaking, the term arm refers to the upper arm only, hence why forearm is a more correct term than lower arm.

The forearm anatomy consists of two elongated bones that run parallel to each other; the ulna, which lies medially; and the radius, which lies laterally. Together, these two bones form the radioulnar joint, which permits supination and pronation of the forearm.

Skin covers these bones, and most people have a higher quantity of hair on the top of their forearm (the posterior compartment) than on the underside (anterior compartment).

The ulnar and radial arteries supply blood to the forearm. The radial artery supplies blood to the posterior and lateral part of the forearm anatomy, while the ulnar artery supplies blood to the anterior and medial aspects [2].

Forearm muscles

The muscles of the forearm are split into two distinct compartments; the anterior compartment, which contains the flexors; and the posterior compartment, which contains the extensors.

The radial nerve supplies the extensor muscles, which are naturally weaker than the opposing flexors, while the median nerve supplies the flexor muscles [3].

Forearm flexors

The forearm flexor muscles
The forearm muscles in the anterior compartment flex the forearm, wrist, and fingers. They also perform pronation, which is to say turning the palm down [4]. They’re divided into three layers; superficial muscles, which lie close to the skin; deep muscles, which lie near to the bones (radius and ulnar) or internal organs; and intermediate muscles, which lie between the superficial and deep forearm muscles.

These lower arm muscles are:

Flexor Carpi Radialis (superficial)
Flexor Carpi Ulnaris (superficial)
Pronator Teres (superficial)
Palmaris Longus (superficial)
Flexor Digitorum Superficialis (superficial/intermediate)
Flexor Pollicis Longus (deep)
Flexor Digitorum Profundus (deep
Pronator Quadratus (deep)

Forearm extensors

The foreaarm extensor muscles
The forearm extensors function to extend the wrist and fingers and are separated into two layers; superficial and deep. While there are only 8 forearm flexor muscles, there are 12 unique forearm extensor muscles, 5 of which originate at the lateral epicondyle of the humerus.

The extensor muscles in the forearm are:

Extensor Carpi Radialis Longus (superficial)
Extensor Carpi Radialis Brevis (superficial)
Extensor Carpi Ulnaris (superficial)
Extensor Digitorum (superficial)
• Extensor Digiti Minimi (superficial)
Anconeus (superficial)
• Brachioradialis (superficial)
Extensor Pollicis Brevis (deep)
• Extensor Pollicis Longus (deep)
• Extensor Indicis Proprius (deep)
• Abductor Pollicis Longus (deep)
• Supinator (deep)

Forearm bones

The forearm bones; the ulna and the radius
Proximally, at the elbow joint, the ulna articulates the humerus.

Distally, it forms a synovial pivot joint with the radius, which allows for pronation and supination. This joint is known as the radioulnar joint, and it helps to keep the ulna and radius together when we move our forearm.

The radius has more articulation points than the ulna. Proximally, at the elbow joint, it articulates with the capitulum of the humerus and the radial notch of the ulna.

Distally, the radius articulates between the carpal bones, the lunate (medially), and the scaphoid (laterally). As mentioned, the radius also articulates with the semilunar notch at the radioulnar joint.

References

  1. Mitchell, B., & Whited, L. (2020). Anatomy, Shoulder and Upper Limb, Forearm Muscles. StatPearls Publishing LLC.
  2. Wikipedia contributors. (n.d.). Forearm. Wikipedia. https://en.wikipedia.org/wiki/Forearm
  3. Boles, C. A., Kannam, S., & Cardwell, A. B. (2000). The Forearm. American Journal of Roentgenology, 174(1), 151–159. https://doi.org/10.2214/ajr.174.1.1740151
  4. Muscles of the Anterior Forearm - Flexion - Pronation. (2020, August 15). TeachMeAnatomy. https://teachmeanatomy.info/upper-limb/muscles/anterior-forearm/

Step-by-step workouts

A man demonstrating the best forearm exercises for mass gainBest forearm exercises and workout routines
A man demonstarting the best forearm workout at home that you can possibly doForearm workouts at home without weights
A man doing some bodyweight forearm exercises during his calisthenics workoutBodyweight forearm exercises for calisthenics
A weight lifter demonstrating the best dumbbell forearm exercises for building muscle during his workoutDumbbell forearm exercises and workouts
A man performing some exercises for his brachioradialis muscleBrachioradialis Exercises and workout

A weight lifter demonstrating how to make your forearms bigger and more muscularHow to get bigger forearms naturally
A man demonstarting some bicep and forearm workoutsBicep and forearm workout routines
A weight lifter doing a bicep tricep and forearm workoutBicep, tricep, and forearm workouts

A weight lifter doing a shoulder and forearms workoutShoulder and forearm workout

A man doing some kettlebell forearm exercises during his workoutKettlebell forearm exercises and workout
A man doing a forearms workout with a backpackForearm workout with a backpack

A lady doing a specific forearm workout for women to gain muscleForearm workout for women

A man performing some forearm extensor strengthening exercisesForearm extensor exercises
A man demonstrating some resistance band forearm exercisesResistance band forearm exercises

A woman trying to get toned forearms by lifting weights with her lower armsHow to tone your forearms

Exercise drills

A man performing dumbbell seated wrist curls to train his forearmsDumbbell wrist curl
A man performing seated barbell wrist curls for his forearmsBarbell wrist curl

A man performing the wrist roller exercise during his workoutWrist roller

A man doing a dumbbell reverse wrist curl over a bench to work his forearmsReverse dumbbell wrist curl
A weight lifter doing a reverse barbell wrist curlReverse barbell wrist curl

A man performing a barbell behind the back wrist curl for his forearmsBehind the back wrist curl

A weight lifter doing a standing wrist curl to work his forearmsStanding wrist curl
A weight lifter doing a standing reverse wrist curl to work his forearmsStanding reverse wrist curl

A weight lifter doing a cable forearm curl during his cable forearm workoutCable wrist curl

A man doing a single dumbbell forearm curlSingle dumbbell wrist curl
A man performing plate wrist curls for his forearmsPlate wrist curl

A man performing palms down dumbbell wrist curlsPalms down dumbbell wrist curls

A man doing a dumbbell wrist twist workout for his forearmsForearm twist exercise

A man doing an EZ bar wrist curl for his forearmsEZ bar wrist curl

Stretches and rehab

A man demonstrating one of the best forearm stretches for loosening up your lower arm musclesBest forearm stretches
A man performing some brachioradialis stretchesBrachioradialis stretch drills

A man doing self myofascial release with a foam roller for his forearmsForearms myofascial release

A man performing a dumbbell wrist flexion for his forearmDumbbell wrist flexion
A man performing a single dumbbell wrist extensionDumbbell wrist extension

A man performing a dumbbell supinator stretchSupinator stretch

A man performing some forearm pronation exercisesForearm pronation and supination exercises
A man demonstarting some good forearm rehabilitation exercisesForearm rehabilitation exercises

A man performing an eccentric wrist flexionEccentric forearm exercises

Common forearm problems

A man with brachioradialis after lifting weightsBrachioradialis pain after lifting
A man with severe weightlifting forearm painForearm pain when lifting weights

A weight lifter showing how you can get forearm pain when curlingForearm pain when curling

A man with shin splints in his forearmsForearm splints
A man showing how to treat common forearm muscle strains with rest, ice, and elevationForearms strains

A man holding his arm after feeling a painful forearm cramping sensationForearm cramping

A man holding his tight forearm musclesTight forearms
A man with weak forearm muscles due to an injuryWeak forearms

A runner with sweaty forearmsSweaty forearms

A thin, small man with very skinny forearmsSkinny forearms
A woman with fat forearms drinking some waterFat forearms

A tennis player holding his racketTennis forearm pain

A man with pain in his forearm when gripping thingsForearm pain when gripping
A man with forearm pain from fibromyalgiaFibromyalgia and forearm pain

A couple playing video gamesForearm pain from gaming

A man with pain in his forearm from typingForearm pain from typing
A man with severe pull up forearm painForearm pain from pull ups

A kettlebell hitting a man's forearmKettlebell hitting forearm

A man with big biceps but small forearmsBig biceps but small forearms
A man showing that he has one forearm bigger than the otherOne forearm bigger than the other

A man with forearm pain due to rowingForearm hurts from rowing

Forearm products

Two people demonstrating the best forearm exercise equipment for gaining strengthForearm exercise equipment
A man using a forearm rollerWrist roller

A man wearing a forearm tendonitis brace to support his lower armforearm brace

A man wearing his compression forearm sleeveForearm compression sleeve
Man with tape on his armForearm strapping

Man wearing an elbow sleeveForearm weights

A weight lifter using his wrist and forearm blasterForearm blaster

A forearm compression sleeveForearm wraps

A wrist curl machine for working the forearm musclesWrist curl machine

The Grip Freak Hanging Wrist RollerGrip Freak Hanging Wrist Roller

The Rogue wrist roller in actionRogue Wrist Roller

DIY toolsDIY homemade Wrist roller

A man using the Viking Strength Forearm BlasterVikingstrength Forearm Blaster

GD wrist rollerGD Wrist Roller

The Pellor Wrist Roller and its packagingPellor Wrist Roller

The SideWinder Grip TwisterSidewinder Grip Twister


Image showing the Sidewinder Pro Xtreme wrist rollerSidewinder Pro Xtreme
An image showing the Sidewinder Pro PlusSidewinder Pro Plus

The SideWinder RevolutionSidewinder Revolution


The IronMind Twist Yo' Wrist featured imageIronMind Twist Yo Wrist

The IronMind One Wicked Wrist Roller featured imageIronMind Wrist Roller

The 4Arm Strong Arm Pump Device4Arm Strong

A lady using the Black Diamond Grip TrainerBlack Diamond Forearm Trainer

The Marcy wrist and forearm developer in actionMarcy Wrist and Forearm Developer

The Bison-1M Forearm exerciserBison-1M Forearm Exerciser

The Core Prodigy Wrist Blaster featured imageCore Prodigy Wrist Blaster

Sports-specific articles

A baseball player's muscular forearms holding a batBaseball forearm workouts

A bucket of white riceRice bucket workout

A man performing some forearm exercises for tennis trainingTennis forearm exercises

A man making use of his musculaar forearms while rock climbingRock climbing forearm workout

White rice in a wooden bucketRice bucket exercises for climbing

A man demonstrating some good forearm exercises for arm wrestlingForearms exercises for arm wrestling

Advanced forearm guides

A bodybuilder with excellent forearm hypertrophyForearm hypertrophy strategy guide

A man doing occlusion training for his forearmsForearm occlusion training

A man showing off his impressive forearm transformationThe forearm transformation guide

A muscular arm holding a dumbbellArnold Schwarzenegger forearm workout

A muscular man showing his fistsBruce Lee forearm training

A bodybuilder flexing his armPhil Heath forearms workout

A muscular man holding a dumbbell in his handThe Sylvester Stallone forearms guide
A man working out on the Total GymTotal Gym forearm exercises

A man doing some TRX forearm exercises during his workoutTRX forearm exercises

Forearm FAQs

A man having his forearm circumference measured to see if it's above average in sizeWhat is the average forearm size?

A bodybuilder with some of the biggest forearms in the worldWho has the biggest forearms in the world?
A man demonstrating how to get bigger forearms and wristsHow to get bigger forearms and wrists

A man showing that his forearms are bigger than his bicepsCan you build forearms bigger than your biceps?
A man demonstrating how to get forearm veins that popHow to get forearm veins
A man showing how pushups work your forearm musclesDo pushups work your forearms?

A weight lifter demonstrating how bicep curls work your forearmsDo bicep curls work your forearms?
A man demonstrating how pull ups work your forearmsDo pull ups work your forearms?
A weight lifter showing how bench press works your forearmsDoes bench press work your forearms?

Powerlifting gripping a barbell in preperation for the deadliftDoes the deadlift work your forearms?
A man demonstrating how wrist curls can be badAre wrist curls bad?
A man showing that you can workout your forearms everyday of the weekCan you workout forearms everyday?

A man demonstrating that your foot is as long as your forearmIs your foot as long as your forearm?
A man demonstrating how often to train forearms for the best results (twice per week)How often can you train forearms?
A man showing that forearm exercises are necessary to build lower arm strengthAre forearm exercises necessary?

A man demonstrating the opposite of forearmWhat is the opposite of forearm?
A bodybuilder with forearms like popeyesWhy are Popeye's forearms so huge?
An overweight senior womanWhy do we get forearm and elbow creases?
A man and a woman seeing how long their forearms areWhat are considered long forearms?
A man doing an upper arm vs forearm comparison to highlight the differencesArm vs forearm: What's the difference?
A man lifting a very good wrist curl weightWhat's a good wrist curl weight?
Two men using the Spartan handshakeWhat's the significance of the forearm handshake?
A man flexing his nice forearmsDo girls like men's forearms?
A blacksmith with muscular forearms holding a hammerWhat's the deal with blacksmith's forearms?
A man demonstrating some good wrist curl alternativesWhat are some good wrist curl alternatives?
A man showing his fist to the cameraAre 11 inch forearms normal?
A man showing his 12 inch forearmsAre 12 inch forearms good?
A man having his 13 inch forearms measured and verified by tapeAre 13 inch forearms impressive?
A muscular man displaying his impressive 14 inch forearmsHow big are 14 inch forearms?
A man holding a dumbbell showing his 15 inch forearmHow to get 15 inch forearms
A bodybuilder showing his 16 inch forearmsCan you get 16 inch forearms naturally?
A bodybuilder flexing his 19 inch forearmsWho has 19 inch forearms?
A bodybuilder flexing one of his 20 inch forearmsHas anyone got 20 inch forearms?
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