For the sake of today's talk, here is the post in question, as sent to me by Brian:
Now, the title leads us into a topic that many people have questions about; squat depth in relation to knee damage. As it so happens, many people have questions about what really is the safest depth to which they can squat before the detrimental effects on the knee outweigh the benefits of wiping your butt with the floor mats. For the record, I don't coach my clients to drop their hips lower than their knees; while I am aware that there are people out there at have been doing it with no adverse effects to their joints, it is my belief that the benefits of a squat do not increase as you pass a parallel position. In addition to that, most people lack the flexibility to squat beyond parallel without their pelvis rotating backwards, which places unnecessary stress on the lumbar spine. I could, and likely will, write a whole different article just on the LPHC movement patterns during squats. That being said, let's take a look at what this Reddit user has to say about the "key points to a deeper, stronger squat."
1) Wear the Right Shoes
Very true! Footwear can help or hinder your squat, and it is important that you make the right decision in this department. Running shoes, or anything with a lift in the heel, generally are not your best option. They change the mechanics of your squat by pushing your forward onto the balls of your feet, and also tend to not be very structurally secure. Opting for a show that has a more neutral (flat) positioning sets you up for a better squat. If you have ankle mobility issues, there are ways to help achieve a proper depth, but more on that later.
2) Start With the Proper Stance
This is also true, but I disagree with the coaching queues that are given. A shoulder width (or slightly wider than) stance is where most people will and should start, not out in a sumo stance. Beginners to the squat very likely do not have the adductor strength to hold proper form in such a wide position, and in many people this creates more impingement in the anterolateral section of the hip joint. There is plenty of literature out there about the angle of the femoral head and it's effects on squat technique from person to person. It's true that this development will effect your squat pattern, but for a large portion of the population, a standard width with feet externally rotated about 15 degrees is going to do the trick nicely. Once my client has a better sense of control in the traditional squat, I would then introduce width variations.
3) Elevate Your Heels
If Spoiler Alert: This part annoys me the most. Our author writes that "this will help your ankles increase their mobility and allow you to get down much lower" This statement is quite simply wrong - lifting your heels is compensating for poor ankle mobility, and will never ever increase your ankle range of motion. I promise you. And for God's sake, a 2x4?!? Think about it - if this were true, every Olympic lifter would be strapping on high heels and banging out new PRs in their squats, and then exclaiming how mobile their ankles had become since they started cross-dressing.
When squatting, look at yourself head-on in the mirror; are your feet collapsing in at your arches? Are your knees ducking together as you come down? These may both point to ankle mobility issues, and can pretty easily be addressed. If you do have tight calf muscles that are preventing you from achieving proper squat form, your best bet is to start stretching your calves with ankle glides (demo video here: http://goo.gl/XgqnNP) and work your way into a proper squat pattern. Heel lifts are best reserved for working around an injury (feel free to message me for more details here) and at MOST kept to a 5lb plate height.
4) Practice Without Weight
Here's a suggestion that I can get behind, finally! When you are new to the world of weight lifting, it is best not to jump into any lift with an absurd amount of weight that you are untrained to handle, just because someone with the body you may aspire to have is using it. However, I would not give the novice lifter the advice to "push your knees out with your elbows at the bottom of the squat." For someone new to squatting, this is likely going to put them into spinal flexion - something that we trainers very much want our clients to avoid. Instead, squat in front of a mirror and notice the orientation of your knees throughout the squat. Do they duck in? Correct the movement during the squat so that they stay in line over your feet the whole time.
5) Use a Barbell
Sure. Or dumbbells, if you want. Some people starting out may have compromised shoulder mobility, and holding the barbell in place can cause them discomfort. In these situations I would stick to holding dumbbells at their side, and progress up to goblet squats, then dumbbell front squats, and then barbell squats. During this time of progression it would be wise to work on pectoral and lat mobility by stretching, foam rolling, or seeing a massage therapist.
6) Protect Your Knees and Grow
Let's address this one step at a time. First, I don't like the phrasing in the statement of "deeper squats recruit more and more muscle fibers in your hips and hamstrings." Muscle fiber recruitment is determined by the load placed on the muscle, not the range of motion it needs to achieve. Your central nervous system (or CNS) can increase the strength of a muscular contraction by increasing the number of active motor neurons (known as spatial recruitment) and by increasing the firing rate of individual motor neurons to optimize the total muscular tension generated (known as temporal recruitment). At lower levels of muscular strength, your primary mechanism is individual motor neuron recruitment. When you approach total motor neuron recruitment, increasing the firing rate takes over as the primary method of muscle strength increase. Short version; muscle fiber recruitment increases with load applied, not necessarily motion generated. Your hamstrings (and quads, and glutes) will recruit motor neurons in a squat relative to the the weight you carry, regardless of whether you break horizontal with your thigh or not. To clarify this training principle, I do want my clients to train motions using a full range of motion (ROM), but that does not mean that 'maximal muscular ROM' is needed. Think about a pushup; you go through a "full range of motion", yet the pecs never achieve their full ROM because you aren't crossing your arms in front of your chest. So the term "Full range of motion" becomes more subjective. Let THAT mess with your head...And additionally, growth hormone production is effected by your stress levels, your sleep, level of exercise intensity, and glucose levels in your blood. Not by whether your femur breaks the horizontal plane in a squat. I'm going to get some people attacking this statement with their opinions, but that's just science.
TLDR; squat with weight you can appropriately handle in a range of motion that your body can achieve without compromising form and/or structural integrity.