BicepsMachineBeginner

How to Use the Bicep Curl Machine

By Bryan Alger, Co-Founder of Gravitus

· Updated Sep 30, 2026

A bicep curl machine, or arm curl machine, is a seated biceps machine with your upper arms resting on a sloped pad. Set the seat so your elbows line up with the machine's pivot, curl the handles up and lower to straight arms. It trains the biceps and brachialis. Most lifters do 3 sets of 8 to 15 reps.

Sets x reps 3 x 8-15

Median 10-rep weight 8035 lbkg men 37.517 lbkg women

Muscles Biceps, brachialis, brachioradialis

Setup Elbows level with the pivot

Bicep Curl Machine start and top positions

1Start. Seat set so your elbows line up with the machine's pivot, the backs of your upper arms flat on the pad, arms almost straight.
2Top. Curl by bending only at the elbows until your forearms are close to vertical, then lower to straight arms over 2 to 3 seconds.

Watch 3 video demonstrations

Video 1 of 3

Find more video demonstrations in the Gravitus app

Technique

How to use the bicep curl machine

Set the pin to a weight you can curl for at least 8 strict reps.
Sit down, rest the backs of your upper arms on the pad and move the seat until the middle of your elbow sits level with the machine's pivot, the axle the handles turn on (see below).
Take the handles palms up with your wrists straight. If the handle arm adjusts, set it so the handles sit in your palms with your arms almost straight.
Curl the handles toward your shoulders by bending only at the elbows. Stop when your forearms are close to vertical and squeeze for a second.
Lower over 2 to 3 seconds until your arms are straight, and stop just before the plates touch the stack.

Setup

How to set the seat height

Set the seat so your elbow joint lines up with the machine's pivot, the axle the handle arm turns on. Manufacturers print the same rule: the Life Fitness Circuit Series manual says to align your elbows with the axis of rotation, and Spirit Fitness says its seat adjustment exists to line the elbows up with the machine's axis. Look from the side: the center of the pivot should sit level with the middle of your elbow, not your armpit.

When the two line up, your forearm and the handle arm turn around the same point, so the handles stay put in your hands and the cam loads the rep the way it was built to. When they do not, the handle travels a different arc from your hand. It slides in your palms, pulls your elbows off the pad partway up, or jams your wrists at the top. Many guides, including our old one, say to line the pivot up with your armpits or shoulders. That is the setup for the pad, not the pivot.

Quick check

Set the lightest pin and do two slow reps. If the handles slide in your hands or your elbows lift off the pad, move the seat one notch and try again.

Equipment

Which curl machine you have

Most gymsPreacher pad, weight stackUpper arms on a sloped pad, a bar or two handles on one arm. The cam decides where the rep is hardest.

One arm at a timeIndependent handlesEach handle moves on its own, so a weak side cannot hide. Log one arm or both, the same way every time.

Plate-loadedLever machinePlates hang on a lever instead of a stack. Where they sit on the lever sets the curve, and the plate total does not compare with a stack.

Palms facingHammer grip handlesNeutral handles shift work from the biceps to the brachialis and brachioradialis.

The cam is the part that shapes the rep. A dumbbell curl is hardest when your forearm is level with the floor. A cam changes its leverage through the rep so the load can peak somewhere else, and the stack pulls from the first inch. When researchers measured eight cam knee extension machines from six brands, resistance changed by as much as 38% across the range, the curves varied widely between brands and none matched the muscle's own strength curve (Folland 2008). Biceps curl machines have barely been measured, so expect the same differences: note where the rep gets hard on yours. A palms-up grip drew 12% more biceps activity than a neutral grip (Coratella 2023).

Gravitus data

How much weight should you use on the bicep curl machine?

On Gravitus, the median man lifts 80 lb (35 kg) for 10 reps on the bicep curl machine, and the median woman 37.5 lb (17 kg).

Men, typical 80 lb for 10 reps

Most lift: 60 to 100 lb
Top 10% lift: 130 lb or more
Starting out: under 60 lb

Women, typical 37.5 lb for 10 reps

Most lift: 27.5 to 50 lb
Top 10% lift: 60 lb or more
Starting out: under 27.5 lb

Men, typical 35 kg for 10 reps

Most lift: 27.5 to 47.5 kg
Top 10% lift: 57.5 kg or more
Starting out: under 27.5 kg

Women, typical 17 kg for 10 reps

Most lift: 13 to 22.5 kg
Top 10% lift: 27.5 kg or more
Starting out: under 13 kg

One-rep max / 10-rep weight, rounded to 5 lb (2.5 under 40). From 9,104 men and 1,426 women who log the bicep curl machine on Gravitus, computed Oct 4, 2026 (Brzycki). Methodology
Percentile	Men	Women
25th	80 / 60 lb	37.5 / 27.5 lb
Median	105 / 80 lb	50 / 37.5 lb
75th	135 / 100 lb	65 / 50 lb
90th	170 / 130 lb	80 / 60 lb

One-rep max / 10-rep weight, rounded to 2.5 kg (1 under 20). From 9,104 men and 1,426 women who log the bicep curl machine on Gravitus, computed Oct 4, 2026 (Brzycki). Methodology
Percentile	Men	Women
25th	35 / 27.5 kg	17 / 13 kg
Median	47.5 / 35 kg	22.5 / 17 kg
75th	62.5 / 47.5 kg	30 / 22.5 kg
90th	77.5 / 57.5 kg	37.5 / 27.5 kg

These are stack numbers, and they do not compare between brands. The stack pulls through a cable, a cam and a lever before it reaches your hands, so the same pin can feel very different from gym to gym, and on most machines one pin loads both arms. At the median, Gravitus lifters log more on the bicep curl machine than on a barbell curl, a sign that the pin is not the load at your hands. Compare yourself to your own log on the same machine and seat notch.

Research

What the research says

Five claims that most bicep curl machine guides repeat, including our old one:

Machines give constant tension. The pin stays the same, but the cam changes the load through the rep. On eight cam machines, resistance changed by as much as 38% across the range (Folland 2008). The stack does keep the bottom of the rep loaded, where a dumbbell curl hangs slack.
The cam matches your biceps' strength curve. In the same study, every machine's curve was flatter than the strength curve of the muscle it trained and significantly different from it (Folland 2008).
Machines build less muscle than free weights. In a meta-analysis of studies lasting 6 weeks or more, free-weight and machine training built muscle the same (Haugen 2023). Over 8 weeks, biceps thickness grew with no difference between a machine group and a free-weight group (Schwanbeck 2020).
Stop short of straight arms to keep tension. The stretched bottom of a curl has the best growth evidence. On a preacher bench, training only the bottom half grew the biceps near the elbow more than the top half, and raised the full curl max more (Pedrosa 2023). In a review of 11 trials, full range and bottom-half partials grew the biceps more than top-half partials (Kassiano 2023).
It builds the biceps peak. With your arms on a pad in front of you, the extra growth shows up near the elbow. Preacher curls grew the elbow flexors more near the elbow and incline curls more near the shoulder (Kassiano 2025).

Anatomy

Muscles worked

Biceps, long and short headBend the elbow and turn the palm up. Both heads work in every curl.

Primary

BrachialisBends the elbow in any grip, under the biceps.

Primary

BrachioradialisThe forearm muscle that helps bend the elbow, more with hammer grip handles.

Secondary

Forearms, front deltsGrip the handles and keep your upper arms pressed into the pad.

Stabilizer

Compare

Bicep curl machine vs preacher curl vs dumbbell curl

Attribute	Bicep curl machine	EZ-bar preacher curl	Dumbbell curl
Upper arm	On a sloped pad	On a sloped pad	At your sides
Hardest point	Set by the cam	A third of the way up, bottom loaded	Halfway, nothing at the bottom
Setup	Elbows level with the pivot	Armpits on the top of the pad	None
Weight jumps	5 to 10 lb per pin	2.5 lb or less	5 lb per hand
Best for	Sets to failure, drop sets	Heavy bottom-loaded reps	One arm at a time, full supination

Verdict

Close to a tie for growth. Machine and free-weight training built muscle the same in a meta-analysis (Haugen 2023). The machine makes it easy to stay strict near failure and to drop the pin for a drop set. Pick the one you can keep adding weight to, or use two.

Programming

Sets, reps and progression

3Sets

8-15Reps

0-2Reps left

Stop each set 0 to 2 reps short of failure. Sets taken close to failure build muscle across a wide range of reps (Schoenfeld 2021), and a machine is a safe place to get there because nothing can fall on you.

A 5 to 10 lb pin jump is big for a small muscle. Add reps first: when every set reaches the top of your range, move the pin down one plate and drop back to the bottom of the range. Keep the same seat notch, or the new number means nothing.

Form

Common mistakes

Seat set to your armpits, not your elbowsThe handles slide in your hands and your elbows lift partway up. Move the seat until your elbows sit level with the pivot.
Stopping short at the bottomThe stretched part of the rep has the strongest growth evidence (Pedrosa 2023). Lower until your arms are straight, then start the next rep.
Elbows or shoulders lifting off the padYour shoulders start to help and the curl turns into a shrug. Go a pin lighter until your upper arms stay down.
Leaning back to finish the repYour torso lifts the weight, not your biceps. Sit tall with your chest against the pad and stop where your elbows stop.
Bending your wristsCurling the wrists at the top hands the work to your forearms. Keep your wrists straight and let the elbows do the bending.

Variations

Bicep curl machine variations

Machine preacher curlThe same idea on a steeper pad. Gravitus tracks it as its own exercise, so log each machine the same way every time.

Single-arm machine curlOne arm at a time on an independent-handle machine. Evens out a weak side.

Hammer grip machine curlPalms facing each other. More brachialis and brachioradialis, less biceps.

Preacher CurlThe free-weight version on a Scott bench. Loaded near the bottom, where the biceps is stretched.

Cable CurlA low pulley instead of a cam. Where you stand sets where the rep is hardest.

Bayesian Cable CurlFacing away from a low pulley with your arm behind you. Pairs well with a machine curl, which keeps your arm in front.

FAQ

Questions people ask

What is the bicep curl machine called?

Gyms and brands call it an arm curl machine, a biceps curl machine or a machine preacher curl. Life Fitness sells it as the Biceps Curl, and many brands call it an Arm Curl. They all work the same way, with your upper arms on a pad and the elbows on a pivot.

How do I adjust the seat height on a bicep curl machine?

Sit with the backs of your upper arms on the pad and move the seat until the middle of your elbow sits level with the machine's pivot, the axle the handles turn on. Manufacturers such as Life Fitness give the same rule. If the handles slide in your hands during a slow rep, move one notch and try again.

Does bicep curl machine work forearms?

A little. The brachioradialis, a forearm muscle, helps bend the elbow, and your grip muscles hold the handles. It is not a forearm exercise, though. For more brachioradialis, use hammer grip handles, and for the wrist muscles, add wrist curls.

Is the bicep curl machine effective?

Yes. In a meta-analysis, machine and free-weight training built muscle the same (Haugen 2023), and over 8 weeks biceps thickness grew with no difference between a machine group and a free-weight group (Schwanbeck 2020). Set it up with your elbows on the pivot and use the full range.

Is the bicep curl machine better than dumbbell curls?

Not for growth; they build the biceps about equally. The machine keeps the bottom of the rep loaded and makes strict sets to failure easy. The dumbbell lets you turn your palm fully up and needs no setup. Many lifters use both.

How much weight should I use on the bicep curl machine?

For 10 reps, the median on Gravitus is 80 lb (35 kg) for men and 37.5 lb (17 kg) for women. The strongest quarter lifts 100 lb (47.5 kg) and 50 lb (22.5 kg) or more.

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References