The Bayesian curl is a single-arm cable curl performed facing away from the cable stack. The cable runs from behind you, so your upper arm sits slightly behind your body and the biceps is still under load when the arm is straight; as you curl, you lean forward a little, and as you lower, you lean back.
It is credited to Menno Henselmans, the Dutch physique coach, whose article calls it his favourite biceps exercise; the name comes from his former brand, Bayesian Bodybuilding, and says nothing about the movement. Brolic lists it as Bayesian Curl (Cable), with “Cable Bayesian Curl”, “Face Away Cable Curl” and “Behind the Back Curl (Cable)” as aliases, and logs it as a one-sided exercise: one set covers both arms, and reps are counted per arm.
Muscles worked
Brolic tags the biceps as the primary muscle group and lists no secondary. Henselmans’ argument is about length. The biceps also crosses the shoulder, so letting the elbow drift forward shortens it, and he says the biceps produces the most active tension when stretched and loses most of it when shortened, the short head by about 80%.
Two 2025 studies name the lift, both found by a PubMed search on October 7, 2026. Attarieh and colleagues had 15 men train one arm with a cable preacher curl and the other with a Bayesian curl for ten weeks, matched for resistance profile; both grew and got stronger, with no significant difference. Parpa and colleagues recorded higher biceps activity in a dumbbell curl than in a Bayesian curl at 80% of each lift’s maximum. Henselmans leans on a 2021 study by Sato and colleagues in which curls trained through the straighter half of the range grew more than curls through the bent half, but it did not use the Bayesian curl. Nothing yet shows it builds more biceps than other curls.
Set up the cable
Set the pulley low or at about elbow height. Coach Ty of MuscleWiki uses either. Elbow height, he says, gives more tension with the arm straight, but the cable then hits your forearm as you curl, so you must lean forward slightly as you curl and back as you extend.
Face away and find your distance. Henselmans has you step forward, away from the stack, if you feel no stretch at the bottom, and step back toward it if the bottom pulls your arm back. Coach Ty takes a staggered stance, working-side leg forward, and says either leg works.
Keep the elbow at your side. Henselmans names letting the weight drag the elbow back as a mistake: with the arm in line with the cable, the moment arm is zero. Coach Ty’s version is not to let the arm track behind you, and to keep the shoulders square rather than twisting toward the stack.
Perform the curl
Curl to a full contraction, leaning forward slightly as you do. Henselmans calls it a waiter’s bow: the lean adds tension at the top, where a cable from behind would otherwise go slack. If you already feel a full contraction without moving, he says that is fine. Then lean back as you lower to a full stretch.
Never let the cable touch your forearm. Both coaches say it. Henselmans’ reason is that a forearm in line with the cable drops the tension to near zero; if it touches, you are not leaning forward enough.
Do not treat it as a strength exercise. Henselmans calls it a pure, advanced bodybuilding exercise: no cheating, no shortened range, no chasing the stack.
How it differs from other curls
| Dumbbell curl | Cable curl facing the stack | Bayesian curl | |
|---|---|---|---|
| Resistance comes from | Gravity | A cable in front of you | A cable behind you |
| Load with the arm straight | Close to none (Henselmans) | Low (Henselmans) | High; the reason for the exercise |
| Where the load peaks | About 90° of elbow bend (Henselmans) | Depends on pulley height | Adjusted by the lean |
The table is one coach’s biomechanics; the only trial to test the idea found a resistance-matched preacher curl just as good.
Logging
One logged set covers both arms, and the rep count is per arm: 10 means 10 on each. Enter the stack weight and note the pulley height and your distance from the stack, because both change the resistance at your hand; a stack label only means something on one machine. The free workout log holds the setup notes, and the weekly set tally shows what your biceps already get.
Common questions
Is the lean cheating? Henselmans says the opposite: cheating is leaning back to swing the weight up; the Bayesian lean goes forward on the way up to keep tension at the top.
My shoulder or elbow hurts at the bottom. Henselmans’ fix for a bottom position that is too hard is to step closer to the stack. If it still hurts, stop; pain is not a cue.
Sources and method
- Menno Henselmans: Bayesian curls, the best biceps builder — definition, rationale, distance and lean cues, the three mistakes; read from an archived copy.
- Menno Henselmans: The perfect biceps exercise — the demonstration, a fragment of a Jeff Nippard video; captions.
- Menno Henselmans: rebranding update — retiring the Bayesian Bodybuilding name.
- MuscleWiki, Coach Ty: Bayesian curl masterclass — cable height, stance, elbow path and shoulder position; captions.
- Attarieh et al. (2025) — preacher versus Bayesian cable curls, ten weeks, 15 men.
- Parpa et al. (2025) — biceps activity in dumbbell versus Bayesian curls, 11 volunteers.
- Sato et al. (2021) — curls trained at 0–50° versus 80–130° of elbow flexion; cited by Henselmans.
- Brolic catalog — name, aliases, one-sided logging and muscle tag.
Cues are the two coaches’ instructions, not optima from a trial, and no comparative growth claim is made against other curls.
