Hammer Strength Plate Loaded Iso-Lateral Kneeling Leg Curl

The Hammer Strength Plate Loaded Iso-Lateral Kneeling Leg Curl is a leg curl machine that lets you train your hamstrings in a standing kneeling position, with your knee in line with the pivot point of the machine. You train one leg at a time, so your strong side cannot take over the work of your weaker one. Intended for the serious home gym, the personal training studio or the semi-professional space where the posterior chain is a fixed part of the programme.

Iso-Lateral Kneeling Leg Curl at a glance

• Knee in line with the pivot point: the kneeling position lets your joint line up with the axis of the machine, so the resistance acts exactly where the hamstring works.
• One leg at a time: you train one side at a time, so left to right differences come to light instead of being masked.
• Rotating knee pad: your supporting leg rests on a pad that moves with you, so you stay stable while the working leg goes through its full path.
• Solid elbow pad with handles: your upper body is held in place, so you cannot swing your back or hips into it to get the weight up.
• Starting resistance of 3.6 kg per side: low enough to learn the movement calmly before you begin loading.
• Loading up to four 10 kg plates per side: suited to an isolation exercise where technique counts for more than maximum weight.
• Four storage pegs for plates: your weight sits on the machine, so you switch quickly between legs and sets.
• Build height of 124 cm: low enough for a basement or garage where taller strength machines will not go.

Why kneeling curls feel different

With a lying or seated leg curl the trickiest part is often the alignment: your knee ends up just in front of or behind the axis of the machine, so the resistance arrives at an angle. In the kneeling set-up your knee lines up with the pivot point, so the load is right through the whole movement. You also stand upright with your upper body fixed against the elbow pad, which makes it hard to help out with your hips. The first sets therefore feel heavier than the weight would suggest.

Training one leg at a time

Because you curl one leg at a time, you can load and assess left and right independently. If you notice one leg failing earlier, you give that leg an extra set or load it differently for a while. With a two legged leg curl a difference like that stays invisible, while in sprinting and jumping it is very much noticeable. For anyone combining sport with strength training, that is one of the strongest arguments for this machine.

Building up the load

The starting resistance is 3.6 kg per side and you load a maximum of four 10 kg plates per side. That looks modest next to a pressing machine, but here the hamstring works fully isolated and without help from the hip extensors, so the weight needed is lower. Four storage pegs keep the plates on the machine, so switching between the left and right leg does not become an interruption every set. Build up calmly: on this exercise a controlled negative phase does more for you than another plate.

Space and set-up

The machine measures 102 cm long, 137 cm wide and 124 cm high, and it weighs 114 kg. At 124 cm build height and 102 cm long, this is one of the more compact strength machines in this line, which makes it suitable for rooms with a lower ceiling. The frame is built from 11-gauge steel with an electrostatically applied powder coating and the pads are moulded foam, so there is no wrapped filling that starts to shift over time. The feet have holes so you can anchor the machine to the floor.

Worth knowing

Weight plates are not included, and because you load each side you will in practice need them twice over if you train both legs heavily one after the other. Beyond that, this is a machine for a single, isolated exercise: it does not replace a squat or a deadlift, it adds to them. If you only have room for one or two machines, a multi gym gives you more exercises per square metre. The kneeling position also takes a little getting used to if you are used to a lying leg curl.

Frequently asked questions about the Iso-Lateral Kneeling Leg Curl

Which muscles does this leg curl work?

Mainly the hamstrings, isolated and one leg at a time. The kneeling position puts your knee in line with the axis of the machine, so the resistance acts in the right place throughout the movement. The elbow pad and the handles fix your upper body, so you cannot help out with your hips. For complete leg training you would combine this with a pushing exercise such as a leg press or a squat.

How much weight can I load?

Each side takes a maximum of four 10 kg plates. The starting resistance is 3.6 kg per side, so you can start very light and build up in small steps. That range sounds modest, but on an isolated hamstring exercise without help from other muscles it is plenty for most people. Plates are not included and are bought separately.

How much space do I need?

The machine is 102 x 137 x 124 cm. That makes it one of the more compact machines in this line and it also fits a room with a lower ceiling. Do keep space clear at the sides to change plates and to switch from the left leg to the right. At 114 kg unit weight the machine stands stable without anchoring, although the feet do have holes so you can bolt it down.

Is this machine suitable for beginners?

Yes, the movement is easy to learn and the fixed set-up takes the balancing away. Start with the starting resistance of 3.6 kg per side and only add weight once you can cover the whole range under control, including on the way back. The kneeling position takes a few sessions to get used to if you are used to a lying leg curl. That said, this is equipment from the professional segment, so a substantial investment for someone just starting out.

How does this differ from a lying or seated leg curl?

The alignment and the number of legs. In the kneeling set-up your knee lines up with the pivot point of the machine, whereas on a lying version that depends on how you lie on the bench. On top of that, here you train one leg at a time, which brings left to right differences into view. The machine is loaded with plates rather than a weight stack, which feels more direct but does mean changing plates.

What is the knee pad for?

The pad supports the leg that is not working and rotates with the movement. That keeps you stable while the working leg covers its full path, without your hip tilting. Together with the elbow pad and the handles, your whole body position is fixed. That makes it easier to keep the tension on the hamstring instead of watching your posture.