reckonerSeated leg curl
Sit down, curl your heels back under the pad. Sitting up puts your hips bent and your hamstrings already long before the rep starts, which sounds like a detail and is the single best documented reason to prefer one leg curl over another.
Curl hard, lower under control.
- Pattern
- Knee isolation
- Trains
- Hamstrings
- Kit
- Machine leg curl
- Loading
- A weight you choose
- Reckoner prescribes
- 3 sets of 10 to 15 reps at RPE 8
- Progression step
- 5 kg once the top of the range is clean
- Skill
- Simple to learn
- Recovery cost
- Low
Muscles worked
How to do it
Set the seat and the back pad
Sit fully back with your knees level with the machine's pivot. If your knee is in front of or behind the axis, the machine is bending you around a joint you do not have.
Set the pads on your legs
The lower pad just above the back of your ankles, the thigh pad snug across your legs so your hips cannot lift when you pull. Snug, not crushing.
Curl hard, lower under control
That is the cue on your wrist. Pull your heels back and under as far as the machine allows, then take longer to let them back out than you took to pull them in.
Let the legs come all the way back out
Straight, or as near as the machine goes. That long position is where this variation earns its advantage, so cutting it short gives away the reason for choosing it.
What goes wrong
Letting your hips lift off the seat
When the pad is loose or the weight is heavy, the hips come up and the movement stops being a knee curl. Tighten the thigh pad. If your backside is still leaving the seat, the stack is too heavy.
Dropping the weight back out
The return is half the rep and it is free training you already paid for. Letting the stack fall gives that away and lands the load on a straightening knee at speed.
Choosing lying down because it feels more natural
This is the one with the evidence behind it. Twenty adults trained one leg seated and the other lying for twelve weeks, and whole hamstring volume rose 14 per cent in the seated leg against 9 per cent in the prone one1. The difference fell entirely on the two-joint hamstrings, which are the ones the seated position lengthens.
How Reckoner progresses this lift
Six weeks of this lift, from 40 kg, run through the real engine. Nothing below was typed in: the prescription, the decision and the sentence beside it all come from the same code that writes your week.
| Week | Prescribed | What it did |
|---|---|---|
| 1 | 3 x 10 at 40 kg | More reps 10 → 11 repsYou finished every set at RPE 7, with room left in the range, so the reps climb before the load does. |
| 2 | 3 x 11 at 40 kg | More reps 11 → 12 repsYou finished every set at RPE 7, with room left in the range, so the reps climb before the load does. |
| 3 | 3 x 12 at 40 kg | More reps 12 → 13 repsYou finished every set at RPE 7, with room left in the range, so the reps climb before the load does. |
| 4 | 3 x 13 at 40 kg | More reps 13 → 14 repsYou finished every set at RPE 7, with room left in the range, so the reps climb before the load does. |
| 5 | 3 x 14 at 40 kg | Deload 40% of sets offFive weeks of building, then one week lighter. About 40% of the sets come off. The load holds and your reps stay where you earned them, so you keep the strength and lose the fatigue. |
| 6 | 2 x 14 at 40 kg | More reps 14 → 15 repsYou finished every set at RPE 7, with room left in the range, so the reps climb before the load does. The lighter week is over, so this is back to three sets. |
Real engine output, not an illustration. Every row was produced by running the engine itself when this page was generated.
The full rule, and why the reps move before the load does, is in how Reckoner decides to add weight.
Questions people ask
Seated or lying leg curl?
Seated, if you have to choose and both are available. Over twelve weeks the seated leg grew about half again as much as the prone leg, 14 per cent against 91. Both are in the library as separate movements, so running both is also a reasonable answer.
Should I point my toes or pull them up?
Pick one and keep it for the block. Toes pulled up brings the calves into it a little, toes pointed takes them out. Neither choice is worth much next to doing the whole range under control, and changing it mid block makes your own numbers hard to read.
Will Reckoner take this out of my plan for an injury?
No. The library records no restrictions at all against either leg curl, which is unusual for a leg movement and is why they stay available when the hinges do not.
Similar movements
Reckoner eases the load first when this lift stalls, and offers one of these only if it stalls again after that. A lift already as light as your kit goes has no load left to ease, so the offer comes straight away. Each of them has a page.
Sources
- Maeo and colleagues, Medicine and Science in Sports and Exercise, 2021. Greater Hamstrings Muscle Hypertrophy but Similar Damage Protection after Training at Long versus Short Muscle Lengths twenty adults training one leg seated and the other prone for twelve weeks, whole hamstring volume rising 14 per cent seated against 9 per cent prone, the difference falling entirely on the two-joint hamstrings while the one-joint head grew the same either way, and protection against muscle damage being equal