“Never let your knees travel over your toes.” This axiom gets repeated during squats, lunges, or any other movement that requires knee flexion. Many of us have been told it’s unhealthy for the knee joint and can cause injury. We’ve all felt that immense stretch in the knee, quadriceps, and even the lower leg or ankle that’s caused when we bend our knee into excess knee flexion. While the logic here is in trying to prevent injury, the question remains, “Why would humans want to limit the natural mechanisms of the body, specifically end-range knee flexion?”
If you’ve ever walked up or down a flight of stairs, you will notice that your knee is required to travel past the toes in order to accomplish this task. So why is it that coaches don’t want their clients’ knees doing so during exercise? If the task causes pain or feedback, there is definitely room for discussion, as well as room for improvement in the client’s mobility and strength.
Similar logic is also found in the spine. Coaches require clients’ spines to brace into a stable, neutral or slightly extended position under load. This does keep the client safe from injury due to inadequate stabilization of the spine by the use of the trunk muscles. Following the same logic as the knee joint, a healthy, mobile spine shouldn’t just be straight and rigid even while it’s not under load. A healthy spine should flex, bend, and twist through varying degrees of range of motion.
When assessing feedback or pain in the knee joint, often there is an issue somewhere else along the chain, i.e., at the hip or ankle joint. A lack of adequate dorsiflexion in the ankle can actually prevent the knee from traveling forward over the toes, causing the ankle to compensate and collapse; this puts the knee and the entire leg in a disadvantageous position. The same goes for the hip joint. Lack of range in the hip joint can cause compensatory patterns down the stream of the entire leg.
While the issue is likely due to the lack of mobility somewhere else along the kinetic chain, there are still specific limitations that the knee joint presents. Whether in sports, training, or just daily life, how often is the knee actually fully flexed? The answer is rarely, if ever. And how often is the knee fully flexed under load? The truth is, likely even less. So it’s no wonder that when a client jumps into walking lunges, they receive feedback in the very bottom of the eccentric load, and/or the first few inches of the concentric action. This is not because they have “knee issues”; they likely have never accessed this range of motion before. And if the range is never accessed outside of training, trying to access it during training, under load, is often a recipe for pain and frustration. Charles Poliquin has a famous quote: “Strength is only gained in the range it is trained.” If a specific joint is not exposed to new and deep ranges of motion, a human cannot adequately or optimally train that joint to its fullest potential.
Since the common limitations are known (lack of ankle and hip mobility), and the desired outcome is more knee flexion, optimal training requires all of these aspects to be accessed and trained under load. When looking at the ankle joint, a larger degree of dorsiflexion is required to allow the knee to flex forward. While stretches and distractions (the use of resistance to create a “wedge” to separate the joint surfaces from each other) work great for mobilizing the joint, load can still be added here with tibialis raises.
The anterior tibialis is the main muscle that performs the action of ankle dorsiflexion. The tibialis raise allows the client to add load to this muscle and perform eccentric and concentric contractions to further increase the resistance in these deep, new ranges of motion. This exercise can be scaled and performed as bodyweight against a wall, into bodyweight standing on the edge of a box, into loading with a dumbbell or using an actual tibialis raise bar for maximum resistance.
When looking at global access to all of these desired ranges of motion, an exercise that works very well is the ATG split squat. The ATG split squat is a variation of the traditional split squat, but has the client emphasize driving the knee forward over the toe into extreme knee flexion. This exercise is great because it allows the client to access ankle dorsiflexion, knee flexion, and recruitment of the anterior tibialis. It also loads the hip flexors during the eccentric portion, giving the structure more length. This exercise can be scaled and progressed from the use of assistance to aid in this loading/unloading pattern from bodyweight, to holding dumbbells, to finally adding a barbell to either the back or front rack position for maximum resistance.
When dealing with pain or feedback, it is often caused by a lack of mobility in specific or multiple joints. When attempting to move past pain, avoiding it only feeds the issue, because it keeps us out of that range (and pain), but that doesn’t do anything to solve the problem. The solution is finding a safe way to access the ranges that are limited. Once the ranges are accessed, trained, and strengthened, the presence of pain and feedback will largely decrease. One very easy way to get started is to simply walk backward. Walking backward encourages your knees to travel past your toes while keeping all loading forces off of the joint. This can then be progressed to add load via the backward sled drag. As with any exercise prescription, a thorough assessment must be performed to fully understand the extent of any joint limitation.
If you have ever experienced pain while training, or just in daily life, take proactive steps to move past those limitations by scheduling a FREE strategy session with one of our professional coaches and see how we can help put you back on the path of healthy, free movement.