Why ankle stability and mobility matter


Have you ever stopped to think about how your body moves? The joints that pivot and rotate to allow you to walk, run, jump, squat, lunge, deadlift. When you think about all the movements, there’s one major joint that is involved in every single one. Your first thought may be the hip joint, and while that’s obviously a major one, we’re talking about the ankles. 

The ankles are a major load-bearing joint of the body and play an essential role in all aspects of performance, especially for athletes who are running, changing direction quickly, and going through rapid acceleration and/or deceleration; they’re actions that put a lot of stress on the feet and ankles and carry a huge risk of sprain and fracture. 

But despite bearing an incredible amount of weight, the ankles are surprisingly fragile and relatively easy to damage, which means that taking precautionary measures to strengthen and stabilize them is key to avoiding injury. 

Basics of ankle anatomy

Photo source:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4994968/ 

The ankle is a hinge joint that moves primarily in the sagittal (up and down) plane of motion. That means that the ankle has two main movements: dorsiflexion and plantarflexion. You can think of dorsiflexion like taking your foot off the gas pedal or lifting your toes toward the sky while keeping your heel planted on the floor. Plantarflexion is the opposite. You’re pushing on that gas pedal or pointing your toes downward like a ballerina.

For a lot of athletes, poor dorsiflexion is one of the most common ankle immobility issues, which compromises major movements like squatting (when you’re at the bottom of the movement), cleans, forward or backward lunges, and even walking and running. There are two major outcomes of poor mobility in the ankle:

  1. You can’t perform the movements at all
  2. You can perform the movements but form, especially in the hips and low back, is compromised leading to compensation and an increased risk of injury

Generally speaking, lack of dorsiflexion is the result of tight calf muscles that interfere with the ankle's ability to move. A 2015 study published in theJournal of Human Kinetics looked at the impact of lower extremity strength and range of motion on squat depth and found that ankle dorsiflexion mobility was “significantly associated” with better squat performance [1]. They suggested that exercises to increase ROM of the ankle dorsiflexion, hip flexion, and dorsiflexor strength can be beneficial for squat performance.

Why ankle stability and mobility are important

​​Whether it’s a squat, deadlift, clean, jump, lateral shuffle, or virtually any other movement, the ankles are recruited to power you through. But in order to actually complete the movement with proper form, a good range of motion is needed to support the body. This motion typically involves engaging in plantar flexion or dorsiflexion movements, both of which become a big challenge when the ankle is stiff and not able to move through its natural course of movement or range of motion. 

For different exercises, the force on the ankles varies [2]. In normal walking, the ankle sustains five times the person’s body weight, whereas with running, this force increases to 13 times their weight. Even at rest when the joint is in a static position, it still provides some level of support to the rest of the body, which means that strength and stability are key for keeping the body in the proper alignment and position. 

But it’s not just walking and running that immobile ankles impede on. Sports performance also takes a big hit. As mentioned before, athletes with poor range of motion in the ankles experience major impediments to squat depth. Think of it this way. A lot of people associate “ass to the grass” squatting with good hip mobility, but it’s not all in the hips. The inability to break parallel actually results primarily from poor ankle mobility, which interferes with the ability to move past a certain threshold. If you improve the range of motion in the ankles, however, along with good hip mobility, you’ll likely find that your squat depth will increase substantially. 

If you can picture this, the human body is like a stack of joints that alternate between mobility-based needs and stability-based needs. The ankle’s primary need is mobility, while the knee’s primary need is stability. Similarly, the hip’s primary need is mobility while the lumbar spine needs stability. If a “mobile” joint loses range of motion, the “stable” joint attempts to compensate for this loss of motion, which ultimately affects the entire chain of stacked joints above and below that one joint. Knee pain (a stable joint), for example, doesn’t generally stem from the knee itself but rather one of the joints above or below the knee joint; typically this is the hip or ankle, both of which are mobile joints.

Long story short, mobility of one joint doesn’t just affect that joint alone--it affects every other joint in the kinetic chain. So, including mobility work into your training program can drastically reduce the risk of an ankle injury, as a strong ankle is far less susceptible to sprains and strains. Poor plantar flexion and dorsiflexion can also affect the rest of the body, as dysfunction of the ankle and foot can lead to pain that extends into the lower leg, knee, hips, and more.

What causes poor ankle mobility?

Poor ankle mobility can be caused by a number of different factors, but most often it’s the result of a general lack of flexibility in the calf muscles, ankle joint issues (or stiffness) from a previous injury, or frequent wearing of high heels. However, research suggests that poor ankle mobility can also be a genetic thing. Studies link the presence of specific alleles with an increased risk of injury. More specifically, people with allele chr21:47156779:D are 1.86x more likely to suffer an ankle injury, and those with the rs13286037 allele have a 1.58x greater risk of injury [2].

Other research has also shown poor ankle mobility is connected with [3]: 

  • Gender and age – Younger females tend to have better ankle ROM than young males, while older males have better ROM than older females
  • Health status – Pre-existing conditions like osteoarthritis can reduce ankle mobility and increase injury risk
  • Biomechanical dysfunctions – Movement-related dysfunction and imbalances can increase the risk of ankle sprains and other injuries

Poor ankle mobility can also be the result of a lack of strength in the muscles surrounding the ankle. A 2017 study published in theJournal of Physical Therapy Science found a moderate correlation between ankle dorsiflexor strength and dorsiflexion range of motion, as well as a correlation between ankle dorsiflexor strength and first toe flexor muscle strength [4].

For athletes specifically, periods of overtraining or even just intense training and competition can also lead to poor ankle mobility that appears as pain and discomfort in the joint. One study of football players throughout their season exemplified this finding that dorsiflexion range of motion was highest pre-season and decreased mid- and post-season [5].

The good thing, though, is that ankle mobility doesn’t have to suffer. When you can understand why ankle mobility is important and how to improve it, you can seamlessly work exercises into your training to maintain full ROM and reduce the risk of injury.

Testing for ankle mobility

Want to know how mobile your ankles are? There’s a simple test!

Research finds that the normal range of motion for ankle dorsiflexion is between 10 and 20 degrees, while average plantar flexion is between 40 and 55 degrees. If you’re not reaching these angles, chances are your ankle mobility is restricted.

Another good indicator that you have restricted mobility is pain during movement. If you’re experiencing pain during dorsiflexion or plantarflexion, it’s likely that you’re ROM is limited, but it can also be indicative of a foot injury. For example, plantar fasciitis is a common cause of pain that radiates to the ankle. So, if you’re experiencing pain, we recommend booking an appointment with your healthcare practitioner to investigate further.

Additionally, lifting the heels during a squat is another sign that mobility may be hindered. If you want to confirm, place your foot 4-5” from a wall with the entire foot planted on the floor. Keeping your heel on the floor, bend at the knee and try to make contact with the wall. If your knee can touch the wall without any pain, mobility is good. However, if there is pain or tension in the ankle or calf muscle, it’s indicative of an issue with mobility of the ankle.

How to build ankle stability and mobility: A 3-step approach

One: Strengthen for better ankle mobility

Mobility exercises are great for strengthening the ankle joint to increase strength and stability. Some to consider include:

  1. Heel lifts
  2. Toe raises/heel drops
  3. Toe/heel walks
  4. Lunges
  5. Overhead squat 
  6. Ankle flexion exercises (using a resistance band is great for these)

Two: Stretch for increased ankle flexibility

Research finds that static stretching can improve ankle joint dorsiflexion range of motion. Some of the best exercises to do this include: 

  1. Big toe stretch
  2. Toe-wall stretch
  3. Ankle circles
  4. Ankle end-range isometric stretch

Three: Ankle mobility drills 

The final piece of the puzzle for strengthening and stabilizing the ankle joint for improved mobility is to include mobility drills. These are movements that don’t typically fall into the classic “strength” or “stretching” category but are necessary to incorporate if you want to get those ankles stable and mobile.

Ankle jumps and single-leg hops are two great mobility exercises that help to improve poor dorsiflexion. They can be performed on their own or in combination with other movements. 

Our fix: the Mobility Wedge

Elevating the heels during squats and particular exercises allow for greater muscle recruitment, reduces stress on your lower back, and reduces the risks of injury by keeping your posture more upright under load. Check out the Mobility Wedge here

bethany mobility wedge