RIRLift app icon RIRLift

Exercises

Spider curl: how to do it on an incline bench, and what it does for your biceps

Published October 19, 2026

A spider curl is a biceps curl you do lying chest-down on an incline bench with your arms hanging straight toward the floor. Set the bench at about 45 degrees, let a dumbbell hang in each hand, palms up, and curl them toward your shoulders without letting your upper arms move. Because your chest is pinned to the pad, you can't lean back or swing, so the biceps do all of the work, and they are hardest to hold near the top of the rep.

Your last spider curl set

How to do the spider curl

Lying on the bench takes your back, hips and shoulders out of the lift, so there is no way to cheat a rep up. With your arms hanging in front of you, the dumbbells are heaviest when your biceps are fully shortened, which makes it a good partner to curls that load the stretched position, like the incline curl.

Steps

  1. Set an incline bench to about 45 degrees and lie face down on it with your chest on the top of the pad and your feet planted on the floor behind.
  2. Hold one dumbbell per hand with your palms facing forward and let both arms drop vertically toward the floor.
  3. Curl both dumbbells toward your shoulders by bending only at the elbows, with your upper arms pointing at the floor.
  4. Squeeze hard at the top for a moment, with your pinkies turned slightly up toward your shoulders.
  5. Lower slowly until your arms are straight again, and start the next rep without letting the dumbbells swing.

Cues

  • Upper arms stay pointing at the floor
  • Chest glued to the pad
  • Squeeze, then lower slowly

Common mistakes

  • Pulling the elbows back as you curl: that turns it into a row and takes load off the biceps; keep your elbows directly under your shoulders and use lighter dumbbells.
  • Cutting the bottom short: let your arms go fully straight on every rep, or you lose half of the range.
  • Lifting your chest off the pad to get the last rep: once your chest moves, the set is over; record the rep you got cleanly.

Swap for: Preacher Curl, Concentration Curl, Incline Dumbbell Curl

Muscles the spider curl works

Spider curls work the biceps, with the brachialis and the forearm flexors helping. Because the arms hang in front of the body, the hardest point is near the top, where the biceps are fully shortened. That is the opposite of an incline curl, which is hardest at the bottom where the biceps are stretched.

Sets, reps and reps in reserve for the spider curl

GoalSets × repsRIRRest
Build muscle 3 × 10–15 1–2 60–90 s
Use dumbbells light enough that your elbows never leave the vertical line.
Arm-day finisher 2 × 12–20 0–1 60 s
Take the last set close to failure; the bench keeps it safe.
Paired with incline curls 2–3 each × 10–12 1–2 60 s
Do incline curls first for the stretch, then spider curls for the squeeze.

Spider curl variations

  • EZ-Bar Curl start position

    EZ-Bar Curl

    Hold an EZ-bar instead of dumbbells while lying on the bench when you want both arms locked to the same weight.

    Build a session with it
  • Concentration Curl start position

    Concentration Curl

    Brace your elbow against your inner thigh when no incline bench is free; it gives a similar strict, cheat-free curl.

    Build a session with it
  • Hammer Curl start position

    Hammer Curl

    Turn your palms to face each other on the bench when you want more of the brachialis and forearms.

    Build a session with it

Spider curl alternatives

Strict curls with support

  • Preacher Curl start position

    Preacher Curl

    Rest your upper arms on a preacher pad when you want the same strictness with heavier loads and more of the stretch.

    Build a session with it
  • Machine Preacher Curl start position

    Machine Preacher Curl

    Use a preacher curl machine when you want the steadiest curl with no setup.

    Build a session with it

Curls that load the stretch

  • Incline Dumbbell Curl start position

    Incline Dumbbell Curl

    Lie back on the incline bench instead of facing it when you want the biceps loaded in the stretched position.

    Build a session with it

Basic curls

  • Dumbbell Curl start position

    Dumbbell Curl

    Stand and curl when you want to use more weight and accept a little body English.

    Build a session with it

Spider curl vs preacher curl

Both stop you from cheating. A preacher curl rests your upper arms on a pad angled in front of you, so the biceps are loaded hardest near the bottom of the rep, in the stretch. A spider curl hangs your arms straight down, so the load peaks near the top, in the squeeze.

Neither is more effective on its own; they load different parts of the curl. If you only have room for one, pick the one you can do with your elbows truly still. If you do two curls a week, a preacher or incline curl plus a spider curl covers both ends of the range.

Which bench angle to use

An incline of about 45 degrees works for most people: the pad holds your chest and your arms can drop vertically without the dumbbells hitting the bench. A lower angle, around 30 degrees, lets the arms hang a bit in front of you and feels harder at the top. Taller lifters may need to sit higher on the pad so the dumbbells clear the floor.

Questions

Are spider curls more effective than preacher curls?

They are equally useful and load different points. Spider curls are hardest near the top of the curl; preacher curls are hardest near the bottom. Use whichever you can do strictly, or both.

What muscles do spider curls work?

Mainly the biceps, with the brachialis and forearm flexors helping.

Are spider curls good for building biceps?

Yes. They remove all momentum, so every rep is the biceps doing the lifting, and they are easy to push close to failure safely.

Can you do spider curls with a barbell or EZ-bar?

Yes. Lie on the same incline bench and hang the bar below you. A bar locks both arms together; dumbbells let each arm work on its own.

Why are spider curls so hard?

Your body can't help at all, and the dumbbells are heaviest where the biceps are already fully contracted. Expect to use noticeably lighter weights than on a standing curl.

How heavy should spider curls be?

Light enough that your upper arms stay vertical for every rep. Most people use a good deal less than their standing curl weight.