Solid Rock SRX55 prone leg curl, plate loaded, 250 kg

The Solid Rock SRX55 is a plate loaded prone leg curl rated for 250 kg, built on a 3 mm carbon steel frame with 60 mm high density padding. Lying face down is what makes the exercise work: the hip angle is fixed and cannot be opened, so the hamstrings flex the knee without help from the lower back. In a commercial gym the prone position is also the one that shows a coach immediately when a member is cheating, because the hips lift off the pad.

Technical specification

Prone, seated or standing leg curl

The three leg curl variants train the same muscle group at different hip angles, and the difference is not academic. A seated curl works the hamstrings in a lengthened position and tends to produce higher force; a prone curl shortens them at the hip and biases the short head of the biceps femoris. Facilities serving field sport athletes, where hamstring injury prevention is the primary reason the machine is bought, generally want both angles available.

• Prone bench with a fixed hip angle, no lumbar compensation
• 250 kg capacity on standard Olympic plates
• 6205 precision bearings for constant resistance through the full arc
• 60 mm high density padding for comfort under heavy load
• Compact D shaped base, stable during explosive repetitions

Placement and maintenance

Position the SRX55 next to a leg extension or a seated curl to form a knee joint pair, and keep a plate tree within reach; the loading frequency here is high because members progress in small increments. The D base gives a compact footprint, so the machine fits a row of plate loaded stations without dictating the aisle width.

Servicing is limited to the bearings, the pivot axles, the plate horns and the upholstery. Plate loaded construction means there is no cable to fray and no stack shroud to inspect. The pebbled leather cover over 60 mm foam is the part that takes the most contact; wipe it with a neutral cleaner and check the pad fixings during the routine safety walk.

Frequently asked questions

Why prone rather than seated?

Lying prone fixes the hip in extension, which removes the possibility of using the lower back to complete a repetition and shifts emphasis towards the short head of the biceps femoris. Most well equipped strength floors carry both a prone and a seated curl for that reason.

Does the machine protect the knee?

The movement arc is designed to follow knee flexion without forcing the joint beyond its natural path, and the ankle pad position is adjustable to the user leg length. As with any knee dominant machine, correct pad placement during induction is what determines comfort.

Are plates supplied?

No. The SRX55 is plate loaded and quoted without weights, so an existing Olympic plate stock can be used. Plates and a tree are priced separately.