Lying Single Legs Reverse Biceps Curl with Towel
- Target muscle
- Brachioradialis
- Synergist muscles
- Biceps Brachii, Brachialis
- Equipment
- Body weight
- Body part
- Forearms
- Type
- Strength
The lying single legs reverse biceps curl with towel is a bodyweight forearm exercise that primarily targets the brachioradialis, with assistance from the biceps brachii and brachialis. You lie on your back, loop a towel around one foot or ankle, and curl the towel up with a pronated (overhand) grip, working one arm at a time. It requires no equipment beyond a towel and is useful for building forearm thickness and grip strength without loading the spine.
How to do the Lying Single Legs Reverse Biceps Curl with Towel
- 1Lie flat on your back on a mat with your legs extended and your arms at your sides.
- 2Hold one end of a towel in your working hand using an overhand (pronated) grip — knuckles facing up.
- 3Loop the other end of the towel securely around the foot or ankle of the same-side or opposite leg, whichever allows a comfortable line of pull.
- 4Extend your working arm fully so the towel is taut and your leg provides resistance against the curl.
- 5Keeping your upper arm still and pressed against your side, curl your forearm upward by bending at the elbow, pulling the towel toward your shoulder.
- 6Pause briefly at the top when your elbow is fully flexed and the towel is under maximum tension.
- 7Lower your forearm slowly back to the start position, maintaining tension in the towel throughout.
- 8Complete all reps on one arm, then switch sides.
Form tips
- Keep your upper arm pinned to your side throughout the movement — only your forearm should move.
- Maintain a firm pronated grip; letting your wrist rotate to a neutral or supinated position shifts the work away from the brachioradialis.
- Control the lowering phase — a slow, 2–3 second descent generates more tension through the forearm than a quick drop.
- Adjust the slack in the towel before each set so there is tension from the very start of the curl, not halfway through.
Common mistakes
- Rotating the wrist to a supinated (palms-up) position during the curl, which transfers load to the biceps brachii and removes emphasis from the brachioradialis.
- Allowing the elbow to drift forward or flare out, which disrupts the line of pull and reduces forearm activation.
- Using a loose or poorly anchored towel loop, which causes the foot to slip and eliminates consistent resistance through the range of motion.
- Rushing the eccentric (lowering) phase, which sacrifices time under tension — the part of the rep where the brachioradialis benefits most.
- Lifting the head or upper back off the mat to assist the curl, which adds unwanted momentum and reduces isolation of the forearm.
Frequently asked questions
What muscles does the lying single legs reverse biceps curl with towel work?
The primary target is the brachioradialis, the large muscle that runs along the outer forearm. The biceps brachii and brachialis assist the movement as synergists.
Why use a pronated (overhand) grip instead of a supinated one?
A pronated grip places the brachioradialis in a mechanically advantageous position to do most of the work. A supinated grip shifts the load onto the biceps brachii, making the exercise a standard biceps curl rather than a reverse curl.
What kind of towel should I use?
Any standard bath towel or gym towel works. It should be long enough to loop securely around your foot and still allow you to grip the other end comfortably while lying flat. A thicker towel also adds a grip-strength challenge.
How many reps and sets should I do?
For strength and hypertrophy, 3–4 sets of 10–15 reps per arm is a practical range. Because resistance depends on leg position and towel tension rather than added weight, higher rep ranges with a slow tempo are common for this variation.
Can I use this exercise as a substitute for a reverse barbell curl?
It trains the same primary and synergist muscles using the same pronated curl pattern, so it is a reasonable substitute when equipment is unavailable. The main difference is that load progression is less precise — you cannot add small increments the way you can with a barbell or dumbbell.
