Bicep curl machines get a bad reputation in some gym circles. "Free weights are superior," people say. But the reality is more nuanced—machines have specific advantages that can accelerate your arm development when used correctly.
Let me show you how to get the most out of bicep workout machines.
Types of Bicep Machines You'll Find
Seated preacher curl machine: The most common type. Features a pad that supports your upper arms (like a preacher bench) with handles attached to a cable or lever system.
Standing cable curl station: A cable stack with a low pulley. You attach a bar or handle and curl while standing. Technically not a "machine" but functions similarly.
Bicep curl machine (selectorized): Typically a seated machine where you grip handles and curl against a weight stack. Arms are usually positioned at your sides or slightly forward.
Plate-loaded bicep curl: Similar mechanics to selectorized machines but you load plates manually. Often allows heavier training.
Advantages of Bicep Machines
Constant tension: Unlike free weights where tension varies through the range of motion (due to gravity), well-designed machines maintain consistent resistance throughout the curl. This means more time under tension per rep.
Built-in stabilization: Machines eliminate the need to stabilize the weight. This sounds like a disadvantage, but it means all your effort goes into contracting your biceps—nothing is "wasted" on stabilization.
Safer to failure: You can push to true muscular failure without worrying about dropping a barbell or getting stuck under weight. When you fail, you just let go.
Easy progressive overload: Most machines have small weight increments (5-10 pounds). Adding a little bit each session is simple and trackable.
Good for beginners: The fixed movement path teaches proper curl mechanics without the coordination demands of free weights.
Excellent for drop sets and burnouts: Quick weight changes make intensity techniques easy to implement.
Proper Setup and Technique
For seated preacher-style machines:
1. Adjust seat height so your armpits are at the top of the arm pad
2. Your upper arms should rest fully flat on the pad—no gaps
3. Grip handles firmly but don't death-grip
4. Start with arms extended (slight bend in elbows)
5. Curl by contracting biceps, not pulling with hands
6. Squeeze at the top for a one-count
7. Lower slowly—3 seconds minimum
8. Don't let the weight stack touch between reps (maintains tension)
For seated curl machines (arms at sides):
1. Adjust the seat so handles are accessible with arms hanging naturally
2. Some machines have elbow pads—position them so your elbows are fixed
3. Keep your back against the pad throughout
4. Curl through full range of motion
5. Control the negative—don't let the weight drop
Common Machine Curl Mistakes
Wrong seat height: If the pad is too high or low, your shoulders compensate. Take time to adjust properly before every set.
Partial reps: Machines make it easy to cheat range of motion. Go all the way down, all the way up.
Using momentum: Just because it's a machine doesn't mean you can't cheat. Jerky movements reduce bicep work. Smooth and controlled always.
Ignoring the negative: Many people focus only on lifting the weight. The lowering phase is equally important for muscle growth. Slow it down.
Going too heavy: Ego lifting applies to machines too. If you can't control the weight through full range of motion, reduce it.
Programming Machine Curls
As your primary bicep exercise:
• 3-4 sets of 10-12 reps
• Focus on progressive overload (add weight when you can complete all reps with good form)
• Can be done 2x per week
As a secondary/finishing exercise:
• 2-3 sets of 12-15 reps
• After heavier free weight work
• Great for pump and burnout
Drop sets (machines excel here):
• Do a set to failure
• Immediately reduce weight by 20-30%
• Rep to failure again
• Repeat 2-3 times
• Brutal pump, excellent for muscle growth
Machines vs. Free Weights for Biceps
This isn't either/or—both have their place:
Free weights are better for:
• Overall strength development
• Coordination and stabilization
• Exercise variety (more options)
• Training at home with minimal equipment
Machines are better for:
• Isolation and constant tension
• Training safely to failure
• Beginners learning movement patterns
• Drop sets and intensity techniques
• Working around injuries (fixed path is predictable)
Best approach: Use both. Maybe free weights for your primary movements when fresh, machines for finishing work when fatigued. Or alternate sessions. The variety benefits muscle growth.
Making Progress on Machines
Progress on machines follows the same principles as free weights:
Add weight: When you can complete your target reps with good form, add weight next session. Even 5 pounds is progress.
Add reps: Working within a rep range (say, 10-12), you might get 10, 11, 12 over successive sessions before adding weight.
Add sets: If you've been doing 3 sets, occasionally add a 4th set for extra volume.
Slow tempo: If weight jumps are too big, slow down the eccentric. A 4-second negative is harder than a 2-second negative at the same weight.
Track everything: Write down weight, reps, and sets. You can't progressively overload if you don't know what you did last time.
Sample Machine-Based Arm Workout
Biceps:
1. Preacher curl machine: 3 sets x 10-12
2. Cable curl (low pulley): 3 sets x 12-15
3. Machine curl drop set: 1 set x failure, drop 3 times
Triceps:
1. Cable pushdown: 3 sets x 10-12
2. Tricep extension machine: 3 sets x 12-15
3. Overhead cable extension: 2 sets x 15
This provides plenty of volume with the constant tension advantage of cables and machines.
The Bottom Line
Bicep machines are legitimate tools for arm development. They offer constant tension, safe training to failure, and easy progressive overload. The idea that machines are somehow "inferior" to free weights is outdated thinking.
Use machines as part of a complete arm training approach that also includes free weights and compounds. The variety will serve your bicep development better than dogmatically sticking to one type of equipment.