Arms · Elbow extension
Triceps Extension Machine
The triceps extension machine is a seated isolation exercise where your upper arms rest on a pad and you straighten your elbows against a weighted bar or handles. The pad fixes your arms in place, so the triceps do all the work along a guided arc, making it an easy way to train them close to failure.
Also known as: Seated triceps extension machine, Machine triceps extension, Overhead triceps machine
- Muscle group
- Arms
- Movement pattern
- Elbow extension
- Type
- Isolation
- Equipment
- Triceps extension machine
- Difficulty
- Beginner
What muscles does the triceps extension machine work?
Primary movers
- Triceps brachii
Assisting muscles
- Anconeus
- Forearm flexors
The triceps have three heads, and all of them straighten the elbow. With your arms resting on a pad and in front of your body, the lateral and medial heads do most of the work.
The pad stops your shoulders from moving, which removes the chance to cheat by swinging or leaning. Every rep comes from the elbow joint alone.
Alignment is the key. Your elbows should line up with the machine's pivot, otherwise the arc fights your natural movement and feels awkward.
Because the machine holds the load, it is easy to take the set to failure safely and to use drop sets, which suits an isolation movement like this.
How to do the triceps extension machine
Setup
- 1
Adjust the seat so your elbows line up with the machine's pivot when your arms are on the pad.
- 2
Sit tall with your back against the support.
- 3
Place the backs of your upper arms on the pad and grip the bar or handles.
- 4
Select a weight you can control.
Execution
- 1
Press the bar or handles down by straightening your elbows.
- 2
Squeeze your triceps at the bottom.
- 3
Hold briefly.
- 4
Return slowly until your elbows are bent about 90 degrees or you feel a stretch.
- 5
Keep your upper arms on the pad throughout.
- 6
Do not let the stack touch down between reps.
Common triceps extension machine mistakes
Misaligned seat
If your elbows are not in line with the pivot, the arc strains the joint.
The fix: Adjust the seat before starting a set.
Lifting the elbows off the pad
Raising the arms brings in the shoulders and removes triceps tension.
The fix: Keep the backs of your arms flat on the pad.
Using too much weight
Heavy loads cut the range and recruit the shoulders.
The fix: Choose a weight you can lift for 10 to 15 full reps.
Dropping the return
Letting the stack slam back loses the stretch.
The fix: Take two seconds to return.
How many sets and reps?
| Goal | Sets | Reps | Load | Rest |
|---|---|---|---|---|
| Hypertrophy | 3–4 | 10–15 | Moderate, 1–2 RIR | 60–90 s |
| Strength | 3 | 8–10 | Heavy, strict | 90 s |
| Beginner | 2 | 12 | Light | 60 s |
Use it after your pressing work as an accessory. Drop sets and slow lowering phases suit machines well. Add weight when you reach the top of your rep range.
Running the triceps extension machine in your next block? Hercules logs every set, shows last session's numbers before you lift, and suggests when to add weight.
Get it on Google PlayTriceps Extension Machine variations and alternatives
Cable Triceps Pushdown
AlternativeA standing cable isolation with a freer path.
Seated Triceps Dip Machine
AlternativeA machine that presses down like a dip.
Overhead Cable Triceps Extension
AlternativeStretches the long head with the arms overhead.
Skullcrusher
HarderA free-weight extension lying on a bench.
A compound press that loads the triceps heavily.
Frequently asked questions
What does the triceps extension machine work?
The triceps, mainly the lateral and medial heads, with minimal help from other muscles.
Is it better than pushdowns?
It is more stable and easy to load. Pushdowns are freer and need no machine. Both build the triceps.
How do I set up the seat?
Align your elbows with the pivot of the machine and keep the backs of your arms flat on the pad.
How many reps should I do?
10 to 15 reps works well, with a squeeze at the bottom.
Does it work the long head?
Only partly. For the long head, use an overhead movement where the arms are raised.
Hercules tracks every triceps extension machine you log, shows you last session's numbers before you lift, and flags when your progress stalls.
Get it on Google Play