Squats are rightly regarded as the king of all lifts. However, to continually squat into the future, you need to look after your body. Your knees in particular!
To build real leg strength and size you want to squat and you want to squat often. However, it’s all too common to hear “Squats are bad for your knees!”. But are they really? Well the research shows that squats aren’t bad at all. In fact, researchers studied Olympic Weightlifters and found they had significantly thicker and stronger Patella Tendons than the average person. This is despite the Weightlifters typically squatting multiple times per day and repeatedly lifting heavy. How did the weightlifters build such structurally sound knees? Through a gradual build up in load tolerance and by working to build a structurally sound body, with minimal joint restrictions and muscular imbalances.
Excluding load management from program design, knee health primarily comes down to structural balance within the quadricep (front thigh) muscles and a strong Gluteus Medius muscle. Structural balance within the knee refers to the Quad muscles: Vastus Lateralis, Vastus Intermedius, Vastus Medialis and Rectus Femoris. These muscles play a crucial role in leg strength and it’s essential that they each sufficiently distribute the load when required. Often knee issues can develop because the bigger Quad muscle, the Vastus Lateralis excessively dominates the smaller Vastus Medialis (aka the VMO). Likewise, a strong Glute Medius muscle aids knee health by preventing valgus (inwards) collapse at the knees. This ensures the knee “tracks” correctly through the right area, just like a train is designed to stay moving within the tracks. If the knee strays from the tracks, it’s likely to “crash” and develop wear and tear on the key structures. The picture below shows valgus collapse and poor knee mechanics which are recipe for knee pain.
However, for today let’s focus more on the Quad muscles. During the squat movement, the VMO is typically most active during the first 15 degrees of knee flexion and the last 15 degrees. This has important implications for how should train the quads. Ultimately, knee problems arise when the VMO is too weak or firing incorrectly. To prevent this problem you can use specific exercises to increase the strength and activation of the VMO. These exercises can better isolate and overload this muscle and ensure your knees are more structurally sound to handle the demands of squatting. The Peterson Step Up shown below is one such exercise to target the VMO and bring up a weak point.
The Peterson Step Up was developed by Physiotherapist Carl Peterson to strengthen the inner quads (VMO) of his Olympic Skiers. Due to the nature of their sport, the Skiers had extremely well developed lateral quad muscles (Vastus Lateralis) but significantly weaker VMOs. This resulted in numerous serious knee injuries for the Skiers, namely the dreaded ACL tear requiring knee reconstruction surgery. To counter this he introduced the Peterson Step Up, the ultimate knee health exercise.
Beware though, this is a technical exercise, requiring both balance and coordination. Nonetheless, the focus here is to virtually completely isolate the top leg quad by attempting to step only with the top leg.The lower leg is really only there to aid balance and is not meant to be utilised for pushing off. Furthermore, the elevated heel on the top leg with knee positioned over toe is designed to increase the recruitment of the VMO. Finally, the low box is purposely utilised to target the VMO when it is most active during the initial part of the squat or stepping motion.
While the Peterson Step Up is a great exercise, it isn’t the only one you can use. Likewise, the VMO can be trained at both the top and end range of knee flexion. Top range exercises include the Reverse Sled Drag, Low Box Step Ups and Terminal Knee Extensions with Band Resistance. End range exercises include 1 & 1/4 Squats and Cyclist Squats. You can rotate through these exercises depending on your training phase and the state of your knees. If you’re suffering from some knee issues, look to first use Terminal Knee Extensions before progressing to Reverse Sled Drags. The latter are a particular favourite of mine as there is minimal eccentric loading or force absorption due to the rapid movement required. This ensures less wear and tear on the knees whilst still working the quads in a controlled setting.
Bonus tip: Isometrics or pauses during a movement can be a powerful tool to aid muscular activation. When suffering from knee pain, often VMO activation is essentially turned down which can further exacerbate knee issues. To counteract this, you can use an isometric leg extension hold. Here you would pause and hold the movement around 15 degrees off end range and hold for the desired time. This results in increased neural drive to the VMO which essentially better switches on the muscle to do it’s job. The protocol to use here is a simple 2 x 30 – 45 second holds at a moderate intensity before beginning training.
Wrapping it all up, the Vastus Medialis or VMO is a crucial muscle if you want strong, well developed AND healthy knees. Any body can get strong, but the challenge is staying healthy to stay strong, year after year. It’s for this reason that all my personal training clients at Fitness First Bond Street will typically have some form of preventive knee health exercise in their programs throughout the year. Be like Arnold, grow your VMO and build that “tear drop” muscle!