Home Blog Fixing the Flaws: Weak Vastus Medialis Oblique (VMO)

Fixing the Flaws: Weak Vastus Medialis Oblique (VMO)

Written on April 30, 2007 at 4:45 pm, by Eric Cressey

The VMO is important not only in contributing to knee extension (specifically, terminal knee extension), but also enhancing stability via its role in preventing excessive lateral tracking of the patella. The vast majority of patellar tracking problems are related to tight iliotibial bands and lateral retinaculum and a weak VMO.

While considerable research has been devoted to finding a good “isolation” exercise for the VMO (at the expense of the overactive vastus lateralis), there has been little success on this front. However, anecdotally, many performance enhancement coaches have found that performing squats through a full range of motion will enhance knee stability, potentially through contributions from the VMO related to the position of greater knee flexion and increased involvement of the adductor magnus, a hip extensor.

Increased activation of the posterior chain may also be a contributing factor to this reduction in knee pain, as stronger hip musculature can take some of the load off of the knee stabilizers. As such, I make a point of including a significant amount of full range of motion squats and single-leg closed chain exercises (e.g. lunges, step-ups) year-round, and prioritize these movements even more in the early off-season for athletes (e.g. runners, hockey players) who do not get a large amount of knee-flexion in the closed-chain position in their regular sport participation.

Eric Cressey

One Response to “Fixing the Flaws: Weak Vastus Medialis Oblique (VMO)”

  1. Anonymous Says:

    Eric have you tried or heard of a ‘peterson step up’ I
    have had good success with building up VMO strength on this one.
    More dynamically/movement orientated way,(I assume you already know it but will mention it anyway) backwards sled pulling gets them pretty fired up as well, in a non-isolated way, and with contribution from other muscles, but still works quite well.

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