GX-320 Leg Extension — Quadriceps Strengthening for Gait Stability & Mobility

The OG Wellness PREFIT GX-320 is a clinical-grade leg extension machine engineered to strengthen the quadriceps muscles — the primary drivers of knee extension and the most critical lower limb muscle group for gait stability, stair management, and fall prevention. The GX-320 is specifically distinguished within the PREFIT range by its variable resistance mechanism, which reduces resistance towards the end of knee extension — enabling patients to achieve a more complete and clinically beneficial full knee extension than standard fixed-resistance leg extension machines permit.

Designed for preventive care facilities, hospital rehabilitation departments, and physiotherapy clinics, the GX-320 incorporates OG Wellness's full suite of safe-exercise design principles: a forward-tilting seat for easy independent access, fixed-position handles for stability during mounting and dismounting, and fully seated adjustment of both seat position and backrest angle.

Made in Japan | CE Marked | Resistance: 3–78 kg | Variable resistance mechanism | Forward-tilting seat

Variable Resistance Mechanism — Greater Knee Extension, Better Outcomes

Conventional leg extension machines apply fixed resistance throughout the range of motion — meaning the resistance is the same at 30° of knee extension as it is at 90°. Biomechanically, this is problematic: the quadriceps generate maximum torque at approximately 60-70° of knee flexion and significantly less torque near full extension. A fixed-resistance machine therefore limits how far patients can extend because the resistance becomes disproportionate to their available torque at the end of range.

The GX-320's variable resistance mechanism automatically reduces the resistance as the knee approaches full extension — matching the resistance profile to the available quadriceps torque throughout the range. This enables patients to achieve a more complete, clinically beneficial knee extension than they could with fixed resistance, producing greater quadriceps activation across the full range and more effective strengthening of the terminal extension that is most important for gait stability.

Forward-Tilting Seat — Safe, Easy Access for All Users

The GX-320's seat tilts forward to facilitate easy, safe mounting and dismounting — a clinical design feature that significantly reduces the effort required to get onto the machine, particularly for patients with weak hip flexors, reduced knee flexion, or hip and knee arthroplasty. Fixed-position handles at the sides of the seat provide stable handholds throughout the mounting sequence, preventing loss of balance during the transition from standing to seated. Together, the tilting seat and fixed handles make the GX-320 safely accessible for the elderly, post-surgical, and neurologically impaired patients who most need quadriceps strengthening.