Bayesian Curl
The Bayesian cable curl is a single-arm cable curl done facing away from a low pulley, so the working arm starts slightly behind your body. The cable keeps tension on the biceps in the stretched bottom position, where a dumbbell curl goes slack, and the brachialis works alongside it.
Also called: Bayesian Curls, Bayesian Cable Curl, Behind-the-Back Cable Curl, Behind the Body Cable Curl · Equipment: strength · Pattern: pull
Step by step
- Attach a single handle to the lowest pulley. Stand facing away from the stack with the handle in one hand.
- Step forward until the cable draws your working arm slightly behind your torso with the elbow straight. Take a staggered stance for balance and brace your trunk lightly.
- Keeping your upper arm fixed behind your body, bend your elbow to curl the handle up and slightly forward, turning your palm up as you go.
- Curl to a full but comfortable top without letting your upper arm swing forward.
- Bring the handle back down under control until your elbow is fully straight and your biceps is on stretch.
- Start the next rep smoothly from the stretch, without the cable jerking your arm straight.
- After the last rep, let the handle return to the stack under control, then switch arms.
- Upper arm fixed behind your body
- All the way down to a straight elbow
- Control the stretch at the bottom
- Turn your pinky up at the top
- Torso still, no lean
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Biceps brachii: long head | Prime mover | A |
| Biceps brachii: short head | Prime mover | A |
| Brachialis | Secondary | B |
| Brachioradialis | Secondary | C |
| Posterior deltoid | Stabiliser | D |
| Forearm flexors | Stabiliser | D |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Upper arm swinging forward
Fix: Keep your upper arm fixed slightly behind your body for the whole set.
Cutting the bottom of the rep short
Fix: Bring the handle down until your elbow is fully straight on every rep.
Cable yanking the elbow straight
Fix: Control the way down and reverse smoothly at the bottom of each rep.
Pushing the shoulder far behind the body
Fix: Start with your arm only slightly behind your torso, at a comfortable angle.
Leaning forward to finish the curl
Fix: Keep your torso still and upright, and move only at the elbow.
What the research says
Muscle growth · first choiceRehab & prehabGeneral fitnessEndurance
- Load and reps — Research comparing loads finds muscle growth is similar across a wide range of loads when sets are taken close to failure; Bayesian curls are usually done with moderate loads and controlled reps.
- Effort — Studies show sets that finish a few reps short of failure capture most of the growth benefit; true failure adds only a small extra effect.
- The stretched position — Biceps trials find training at long muscle lengths produced more growth than training at short lengths. The cable's steady tension at the bottom is the main reason to choose this curl.
- Shoulder angle — Two trials that matched the resistance found curls with the arm behind the body grew the biceps no more than curls with the arm at the side or in front. An EMG study found less, not more, biceps activity than in a dumbbell curl.
- Volume — Research links more weekly sets for a muscle to more growth, with diminishing returns. Programmes often pair one stretch-focused curl with a curl or hammer curl that trains a different part of the range.
Log the bayesian curl in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.