$ 6,100 excl. tax

The LegExx System comes with everything you need to successfully incorporate flywheel training and its multitude of benefits in your quest to strengthen the quadriceps femoris muscles.

No assembly is required upon arrival, unless you opt for one of the unassembled shipping options, which will include a detailed guide.

LegExx Machine

kMeter II


XL - 0.070 kgm²
- +

SKU: LEGEXX Categories: , , ,


Machine includes:

  • LegExx with
    • Pre-attached Drive Belt
    • Built-in wheels and handles for enhanced mobility
  • kMeter II feedback system
  • XL Flywheel
  • kGrip for eccentric overload training



Multi-exercise devices like the kBox and kPulley have huge benefits in terms of versatility in various settings, whereas single-exercise devices are beneficial when you need to focus on a specific muscle group. The LegExx primarily targets the quadriceps femoris muscles.

For healthy users (injury-free), the general benefit with a leg extension machine is that it allows 100% muscle stimulation by maximizing hypertrophy and strength gains in the quadriceps, without overcompensating with other muscles (e.g. glutes in squats). While for injured or low mobility users (e.g. in rehab for ACL or patellar tendinopathies), the main benefit involves gaining strength in the quadriceps without having to worry about posture or complex poliarticular movements, such as the squat.


The LegExx offers full stimulation over the whole range of motion and in all parts of the quadriceps femoris, both concentrically and eccentrically, thanks to the unlimited and variable resistance of the flywheel. Moreover it is designed to allow users to easily overload themselves in the eccentric phase by simply pulling on a handle without any need for external help.

The phone holder on the LegExx will allow users to comfortably get instant feedback as they train with the kMeter II feedback system.

And lastly the mobility of the LegExx makes it unique in comparison with other leg extension alternatives due to its practical wheels and absence of a weight stack. This makes the machine suitable for flexible facilities, circuit training, and more.

Additional information


LegExx Machine



Shipping options

No assembly (by default), Semi-assembled (detailed guide available), Unassembled (detailed guide available)


Space Grey

Usage area

100 x 139 cm (39.4 x 54.7 in)

Foot print

80 x 108 cm (31.5 x 42.5 in)


110 cm (43.3 in)


95 kg (210 lbs)

Maximum weight allowed

350 kg (772 lbs)

Inertia range (standard)

XS, 0.005 kgm² – XL, 0.280 kgm²


Built-in kMeter II feedback system

Compatible flywheels

XS (0.005 kgm²), S (0.010 kgm²), M (0.025 kgm²), L (0.050 kgm²), XL (0.070 kgm²)

SKU 18282

kMeter II


kBox4 Pro, kBox4 Lite, kPulley2, LegExx

Available for

kBox4 Active


LegExx, kPulley2, kBox4 Active and all kBox4 Lite & kBox4 Pro devices produced since May 2018

Sample rate

10000 Hz (155 revolutions/second)



XL – 0.070 kgm²


kBox4 Pro, kBox4 Lite, kBox4 Active, kPulley2, kPulley Go, LegExx