Training guide
Your forearms grow like any other muscle: load them, add a little more over time, and give it months. In small trials, curls grew the brachioradialis, the big muscle on the thumb side near your elbow, by about 14 to 18% in 12 weeks, and slow wrist curls thickened the muscles underneath by about 7% in 4 weeks. Your pulls and curls already do part of the job; a few sets of direct work do the rest.
This guide covers the forearm muscles, the exercises that build them, how much direct work adds to rows, pull-ups and deadlifts, how many sets and how often, building thicker forearms at home, how long it takes, how to measure them, what genes, bone and sex decide, and how to look after your elbows and wrists.
Curls grew the brachioradialis by 13.5 to 17.6% in 12 weeks on MRI (magnetic resonance imaging) scans, slow wrist curls thickened the wrist flexors by 7.1% in 4 weeks, and finger-flexor training added 0.6 to 0.8 cm to forearm girth in 5 weeks in climbers. All of these were small studies.
Extra wrist and forearm work added wrist strength that the same full-body programme didn't, a forearm block added to pull-ups raised grip 12 to 14%, and arm wrestlers had much bigger forearms than other strength athletes with similar upper arms. No trial has compared forearm size with and without direct work.
Curls in hammer, reverse and Zottman grips for the brachioradialis; wrist curls both ways for the muscles underneath and on top; and carries, hangs or squeezes for the muscles that close your hand. Our forearm workout puts them together.
Of direct forearm work, over 2 sessions, on top of your pulls and other curls. That's our editorial starting point: no trial has tested a forearm dose, so it sits inside the 10 or more sets per muscle a week that grew muscle best in reviews.
Limb girth, the forearm included, was strongly inherited in twins, men had thicker forearm muscles than women even allowing for size, and on the same arm programme some people barely changed while others grew a lot. Your wrist bones don't grow.
Small studies without a comparison group measured under a centimetre of extra girth after 5 to 6 weeks, and scans showed clear growth by 12 weeks. Measure the same way every 4 weeks and compare yourself with yourself.
The muscle on the thumb side of your forearm, with its bulk near the elbow. It bends your elbow in every curl: in 4 men measured with MRI, it did about 19% of the elbow-bending work, alongside the brachialis (47%) and the biceps (34%). Curls grew it in a 12-week trial.
The wrist and finger flexors on the palm side start at the inner elbow. They close your hand and bend your wrist, and the finger flexors do most of your gripping. Our forearm flexors guide has the anatomy.
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The muscles on the back of the forearm start at the outer elbow. They open your hand, lift the back of it, and hold your wrist steady whenever you grip. Reverse wrist curls, reverse curls and the wrist roller train them.
In 42 adults scanned by MRI, the volume of the forearm flexors and extensors tracked grip strength closely. In fencers, forearm strength and size rose together, with the same force for each square centimetre of forearm.
Your wrist is mostly bone, tendons and ligaments, and the forearm muscle bellies sit nearer your elbow, so training thickens the forearm more than the wrist (our reading of the anatomy). We found no study that measured wrist size after training.
In 105 pairs of twins aged 10 to 14, genes explained 87 to 95% of the differences in limb girth, the forearm included, at most ages. Girth takes in bone and fat as well as muscle, so that isn't about muscle alone. Across 24 studies, about 56% of the differences in grip strength were inherited.
In 585 adults on the same 12-week arm programme, muscle size changed by anything from 2% smaller to 59% bigger. In 41 pairs of male twins, genes specific to training explained about 20% of the differences in arm strength gained.
In 50 recreational climbers, men's forearm muscles were thicker than women's even after allowing for body size and training, and men's forearm muscle volumes were larger on MRI. Women and men still grow muscle at similar rates relative to where they start.
In fencers, the sword-arm forearm was larger than the other one, more so than in runners. In professional tennis players, the forearm flexors of the playing arm were 11 to 15% bigger, and in 7 boys who played tennis, the playing arm's forearm flexors were 21% and extensors 25% bigger, against about 3% difference between arms in inactive boys. These are snapshots, not trials, but they point the same way: genes set the start and the pace, and training still moves it.
21 untrained adults trained one arm with incline curls and the other with preacher curls, 5 sets of 10 at 70% of their maximum, twice a week for 12 weeks. On MRI, the brachioradialis grew 13.5% with incline curls and 17.6% with preacher curls, and all the elbow-bending muscles together by 17.6% and 19.2%. It's one trial.
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In a trial of 16 people, slow-lowering wrist flexion 3 times a week for 4 weeks raised wrist flexor strength by 30.8% (people who didn't train lost 7.4%) and their thickness by 7.1% (against a 3.7% loss).
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In 22 advanced climbers, 5 weeks of finger-flexor training twice a week, heavy or light with blood-flow restriction, added 0.6 to 0.8 cm to forearm girth. In 25 recreational athletes, 6 weeks of gym and climbing sessions added 0.5 to 0.8 cm. Neither study had a group that didn't train, so other explanations can't be ruled out.
In 43 teenage baseball players on the same 12-week full-body programme, those who added wrist and forearm exercises gained more wrist and forearm strength, though not more grip. In 30 inactive young men, a forearm block of wrist curls, reverse wrist curls, reverse curls and farmer's walks, added to 8 weeks of pull-up training, raised grip by 12 to 14%, more than pull-ups with core or interval work.
9 arm wrestlers had much bigger forearms than 9 strength-trained athletes, with no difference in upper-arm size or biceps thickness. It's a small snapshot that can't show cause and effect, but it fits the idea that loading the forearm directly adds size.
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Muscle activity studies disagree on whether palms down, thumbs up or palms up works the brachioradialis hardest, as our reverse curl and hammer curl guides explain, and no trial has compared grips for growth. In the one growth trial, palms-up curls grew it well.
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Each extra weekly set added a little more growth across 15 studies, and an overview of 137 reviews found 10 or more sets a week built more muscle. The returns shrink as the sets go up, and sets of other lifts that work a muscle count partly towards it.
Across 28 studies of 747 adults, light, moderate and heavy loads built similar muscle when the sets were hard, and heavier loads built more strength. Stopping a few reps short of failure cost little growth.
With the weekly sets matched, 25 studies found no real difference between training a muscle once, twice or three times a week.
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Curls in any grip grow the big muscle on the thumb side; no grip is proven best. Hammer curls at 3 sets of 10 to 15 and reverse curls at 2 sets of 10 to 15 (our forearm workout); the Zottman curl's move page gives 2 to 3 sets of 8 to 12.
Light and slow: 2 or 3 sets of 12 to 15 each way, stopping 2 or 3 reps short (the starting point our wrist curl guide takes from its version pages). The wrist roller's move page gives 2 or 3 rounds of winding the weight up and lowering it slowly.
3D demoWrist curlsBeginner · A dumbbell
3D demoReverse wrist curlBeginner · A dumbbell + A bench or box
3D demoDumbbell wrist curl over a benchBeginner · A dumbbell + A bench or box
3D demoOne-arm seated reverse wrist curlBeginner · A dumbbell + A bench or box
3D demoWrist rollerBeginner · Other / check instructions + Weight plates
3D demoDumbbell forearm rotationBeginner · A dumbbell + A bench or boxFarmer's carries at 2 or 3 walks of 30 m, hangs of 10 to 20 seconds and ball squeezes of 10 with 5-second holds (our forearm and grip strength workouts); the plate pinch's move page gives 3 or 4 holds of 10 to 30 seconds with each hand.
3D demoFarmer's carryIntermediate · A dumbbell + A kettlebell
3D demoSuitcase carryIntermediate · A dumbbell + A kettlebell
3D demoBar hangIntermediate · Pull-up bar + A step
3D demoPlate pinchIntermediate · Weight plates
3D demoBall squeezeBeginner · Other / check instructions
3D demoBand finger extensionBeginner · A bandAbout 6 to 10 hard sets a week of direct forearm work, curls in forearm-friendly grips plus wrist work, on top of your rows, pull-ups and other curls (our editorial starting point). Our forearm workout, twice a week, gives about 7 sets of curls, 2 sets of wrist curls and 2 carries each time.
Curls of 10 to 15, wrist curls of 12 to 15 slow reps. Stop most sets 1 to 3 reps short of failure; the last set of small moves like these can go to 0 to 2 reps short, as our plans say. In your first two weeks, keep 3 or 4 reps to spare.
60 to 90 seconds between sets, our plans' rest for small moves, or pair a curl with a wrist curl and rest after the pair.
Twice a week, at least a day apart, as our forearm workout suggests. With weekly sets matched, training more often doesn't add growth, and sore elbows need the rest days.
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Add reps, then weight. Forearm muscles are small and dumbbell jumps are big, so reach 15 on every set of hammer curls before the next dumbbell, as our forearm workout suggests. For carries, change the weight or the distance, not both at once.
Use straps only on your heaviest pulls, so your grip still does the work on the rest, as our grip strength guide suggests.
From our forearm workout; the stopping rules are from our plans.
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The movement on the figure: Hammer curl
Hammer and reverse curls, wrist curls with a light dumbbell (a tin of beans will do to start), and carries with shopping bags or water containers cover all three kinds of work.
Hangs from a bar, chin-ups and rows load your grip, but the wrist muscles are hard to progress without some weight, so a light dumbbell or a resistance band helps. Bands built strength like weights and machines across 8 studies.
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Our editorial suggestions: we found no standard method for measuring forearm girth.
Strength comes first. Wrist flexor thickness rose 7.1% in 4 weeks in one small trial, forearm girth rose 0.5 to 0.8 cm in 5 to 6 weeks in two studies without a comparison group, and in a thigh study growth showed on scans from about weeks 3 to 4.
The brachioradialis grew 13.5 to 17.6% over 12 weeks of curls, and years of tennis left the playing arm's forearm flexors 11 to 15% bigger.
The same programme can change one person's arm a lot and another's barely at all. Your own log and tape are the fair comparison.
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Nobody can tell you how big your forearms will get, or when. What you can control is the habit: direct work twice a week, enough sleep and food, and adding reps before weight.
The forearm workout is built for size: curls in three grips, wrist curls and a carry. The grip strength workout and the wrist and forearm routine train your grip and the smaller moves, and the arm and pull sessions work your forearms along the way.
A 25-minute forearm size workout with dumbbells: hammer, reverse and Zottman curls for the big muscle on the thumb side, then wrist curls and a carry.
25 minBeginner7 movesA dumbbell, A kettlebellA 20-minute grip session: warm up the wrists and fingers, train the hand and forearm muscles, then carry and hang to load your grip the way everyday life does.
20 minBeginner10 movesOther / check instructions, A bandWrist mobility and forearm strength for desk work, climbing, push-ups and handstands.
10 minBeginner7 movesA wall, A dumbbellA 25-minute carry workout with dumbbells or kettlebells: farmer's carries, suitcase carries on each side and an overhead carry, with a safe pick-up first.
25 minBeginner7 movesA kettlebell, A dumbbellBiceps, triceps and forearms: curls, hammer curls, skull crushers, pushdowns, concentration curls and dips.
35 minBeginner7 movesA dumbbell, A bench or boxA 30-minute bodyweight arm workout: chin-ups and rows for the biceps, close-grip push-ups and dips for the triceps, and a bar hang for your grip.
30 minIntermediate8 movesPull-up bar, A bench or boxA pull day workout for back and biceps: pull-ups, barbell rows, chest-supported rows, face pulls and curls, with sets, reps and rest.
55 minIntermediate10 movesPull-up bar, A barbellSplit plans give the arms their own day, so the forearm workout fits alongside; the kettlebell plan works your grip through swings and carries.
The classic chest, back, legs, shoulders and arms week, built from our gym workouts, with what research says about training each muscle once.
5 training days45 minIntermediate4 days a weekA 4-day upper/lower split: two upper body and two lower body gym days, each muscle trained twice a week, with sets, reps and progression.
4 training days50 minIntermediate6 days a weekA 6-day Arnold split: chest and back, shoulders and arms, then legs, each twice a week, with paired sets, weekly set counts and shorter 3 and 4-day versions.
6 training days55 minAdvanced3 days a weekAn 8-week kettlebell plan for beginners: two strength sessions and a swing-interval day each week, with how to choose a bell and swing safely.
3 training days35 minBeginner3 days a weekA free 30-day arm challenge with or without weights: three 20-minute sessions a week, rest days, a ladder for every move and honest words on arm fat.
3 training days20 minBeginnerDiscomfort up to about 3 to 4 out of 10 is fine if it settles within an hour and your elbow is no worse the next morning; otherwise go lighter, not to nothing, as our elbow guides say. With pain on the outside of the elbow (tennis elbow), bring reverse curls and reverse wrist curls back last and light. See a GP if it hasn't improved after 2 weeks of rest and looking after it yourself.
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Stop if your fingers tingle or go numb: that's a nerve, not a tired muscle. With carpal tunnel symptoms, the NHS says to cut down on anything that makes you bend your wrist often or grip hard, so leave wrist curls and heavy grip work out until it settles.
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With arthritis at the base of the thumb or pain on the thumb side of the wrist (de Quervain's), skip plate pinches and curl palms up rather than with hammer curls, as our move pages advise.
Women grow muscle at similar rates to men relative to their starting size, though men's forearm muscles are bigger on average. The plan is the same.
Adults over 50 gained lean mass across 49 studies, a little less at older ages. Start lighter, look after your elbows and progress steadily.
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If you get chest pain or pressure, feel faint or dizzy, are unusually breathless, or your heart races or beats irregularly during exercise, as our plans advise.
For chest pain that comes on suddenly and doesn't go away, or spreads to your arms, neck, jaw, stomach or back, or comes with sweating, feeling sick, light-headedness or breathlessness; arm pain that comes on suddenly with pressure, heaviness or squeezing across your chest; severe difficulty breathing; someone who faints while exercising; palpitations that don't go away or come with chest pain, breathlessness or feeling faint; or a headache that starts suddenly and is extremely painful, especially while lifting or straining. Don't drive yourself to A&E.
For severe arm pain that makes your arm hard to move, a snap with your arm changing shape, or an arm that tingles or feels numb after an injury. A pop at the front of the elbow during a curl, with bruising, a gap or a bulge in the upper arm, can be a torn biceps tendon: go the same day, as our biceps guides say. In the US, go to urgent care or the emergency department.
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For severe wrist pain, a snap, grinding or popping noise when you hurt it, a wrist you can't move or hold things with, a wrist that has changed shape or colour, or feeling faint or sick from the pain. Also if your arm hurts when you exercise but the pain goes away when you rest. In the US, contact your doctor or urgent care.
If elbow or arm pain hasn't gone after a few weeks, tennis elbow hasn't improved after 2 weeks of rest and self-care, or wrist pain hasn't improved after 2 weeks of home treatment or comes with tingling or numbness. Numb hands, tingling or a weak thumb can be carpal tunnel syndrome.
Speak to your GP first if you haven't exercised for some time or have a medical condition. Get advice before hard or straining work with high blood pressure that isn't controlled (140/90 or higher at a clinic, or 135/85 at home), heart disease, glaucoma, a hernia or recent surgery, or if you're pregnant. With a pacemaker or defibrillator, the American Heart Association asks you to check with your doctor before upper-body strength training. Breathe out as you lift.
Beat says a drive to be more muscular can be part of an eating disorder, especially in men. Worrying a lot about one part of your body and comparing your looks with other people's can be body dysmorphic disorder, and the NHS lists exercising too much among the signs of an eating disorder. See a GP; Beat's helpline in England is 0808 801 0677, and our eating disorders guide has the other numbers.
Genes shape forearm size and grip strength, and people respond very differently. But forearms grew in the trials that loaded them, and the playing arm's forearm muscles were clearly bigger in tennis players. Genes set the start and the pace; training still moves it.
Pulls and carries load your grip, but extra forearm work added wrist strength and grip beyond what the main lifts gave, and arm wrestlers had bigger forearms than other strength athletes. No trial has compared forearm size with and without direct work.
The muscles that close your hand make up much of the forearm: finger-flexor training added forearm girth in climbers, in a study without a comparison group, and forearm muscle volume tracked grip strength on MRI.
Wrist curls thickened the wrist flexors, but curls grow the brachioradialis, the big muscle near your elbow. Do both.
We found no study of it. Light and heavy loads grow muscle alike when the sets are hard, and training more often adds nothing once weekly sets match. A few hard sets twice a week is plenty.
Your wrist is mostly bone, tendons and ligaments, so training thickens the forearm more than the wrist (our reading of the anatomy). We found no study that measured wrist size after training.
Keep your pulls and curls, and add direct forearm work twice a week: curls in hammer, reverse and Zottman grips, slow wrist curls both ways, and carries or hangs. Build towards about 6 to 10 hard forearm sets a week, adding reps before weight. In small trials, curls grew the forearm's brachioradialis by 13.5 to 17.6% in 12 weeks.
Strength comes first, within weeks. Small studies without a comparison group measured up to about 0.8 cm more forearm girth after 5 to 6 weeks, and scans showed clear growth by 12 weeks. People vary a lot, so expect months and measure the same way every 4 weeks.
Partly: forearm girth was strongly inherited in a twin study of children, and grip strength is about half inherited. But the playing arm's forearm muscles were clearly bigger in tennis players, and forearms grew in the trials that loaded them, so training still makes a real difference.
Hammer, reverse and Zottman curls for the brachioradialis near the elbow; wrist curls and reverse wrist curls for the muscles underneath and on top; and farmer's carries, hangs or plate pinches for the muscles that grip. No single grip or exercise has been proven best, so use the ones your wrists and elbows like.
A pair of dumbbells or a loaded backpack is enough for curls and wrist curls, and shopping bags or water containers work for carries. Without any weight, hangs, chin-ups and rows load your grip, but the wrist muscles are hard to progress, so a light dumbbell or a band helps.
They can: slow-lowering wrist curls thickened the wrist flexors by about 7% in 4 weeks in a small trial. They don't train the brachioradialis, though, so pair them with hammer or reverse curls.
They help, especially if you lift without straps. But in trials, extra forearm work added wrist strength and grip beyond what the main lifts gave, and arm wrestlers had bigger forearms than other strength athletes. If forearm size matters to you, a few direct sets a week are worth it.
It can: the muscles that close your hand make up much of the forearm, finger-flexor training added forearm girth in climbers, and forearm muscle volume tracked grip strength on scans. Our grip strength guide covers training grip itself.
Twice a week suits most people, at least a day apart. When weekly sets are matched, training more often doesn't add growth, and sore elbows need the rest days.
Not much. Your wrist is mostly bone, tendons and ligaments, and the muscle bellies sit nearer your elbow, so training thickens the forearm more than the wrist. We found no study that measured wrist size after training.
Genes, bone structure and body fat all play a part, and men tend to have bigger forearm muscles than women. Many people never train their forearms directly, or always use straps; adding curls in forearm-friendly grips and some grip work is the usual fix.
Discomfort up to about 3 or 4 out of 10 is fine if it settles within an hour and your elbow is no worse the next morning; otherwise go lighter, not to nothing. With pain on the outside of the elbow, bring reverse curls back last. See a GP if it hasn't improved after 2 weeks of rest and looking after it yourself.
Exercise education, not a personal prescription, and clinical review of these guides is pending. Check with a GP before starting hard training if you have a heart condition, chest pain, dizziness or breathlessness when active, and stop for sharp or increasing pain. Health disclaimer.
