Reducing the Risk of Injury: Ankle Mobility


By: O2X Injury Prevention Specialist Joe Cavallaro PT, DPT, SCS, CSCS

“It depends.”

Have you heard this from a Physical Therapist or another medical provider before? It’s a common answer, and I find myself echoing this statement a lot – especially in response to the question, “what’s the best stretch for…? The question isn’t wrong, but the answer is less than helpful unless we take a look at which factors to focus on. It helps to know which are the most important factors for you to address without spending too much of your time just on preparation. This discussion will focus on ankle mobility – what it is, why it matters, and what you can do. 

Most importantly – mobility is the ability of a joint to move. Each joint is connected by two or more bones, held together by ligaments, and driven by muscles. Joint range of motion is dictated by the anatomical shape of each bone and stabilized by stiff ligaments. Muscles provide the first layer of protection to limit any undue stress on the ligaments ensuring the integrity of the joint. Flexibility specifically describes the ability of a muscle to lengthen. Muscles need to lengthen enough to not restrict full joint range of motion but strong enough to provide stability at the end-range of movement.

Whether you serve in the military, law enforcement, fire, or emergency medical service, I’ll make the assumption that you have a solid understanding of each piece of equipment you work with – what it does, how it functions, and when to use it. At a recent drill weekend with an infantry unit from the Army National Guard in Massachusetts, I observed soldiers spending hours preparing for their individual weapons qualification. As they moved through the training stages, they repeatedly assessed the functions of their weapons, practiced positioning and movement, and corrected malfunctions. Professionals spend countless time ensuring that mission essential equipment functions optimally because their job and often their safety depends on it. It should make sense that we take the same care in ensuring our bodies function optimally for the same reasons.  

Structure and Function

The ankle joint is formed where the parallel bones of the lower leg, the tibia and fibula, connect to the top of the talus bone, a dome-shaped bone at the top of the foot. A rudder-shaped heel bone, the calcaneus, sits below the talus. In front of these two are the remaining tarsals, metatarsals, and phalanges that make up the rest of the foot. 

Ankle stability is provided by strong ligaments, which allow for motion in specific directions and restrict motion in others, while forward movement from the ankle is powered primarily by the large calf muscles – the gastrocnemius and soleus. Smaller but more important muscles also cross the ankle joint from the lower leg and help coordinate movement with the foot. Some of these muscles run all the way to your toes. They may be small, but their health and function play a vital role in ankle function. 

The main functions of your ankle joint are propulsion and accommodation. Propulsion creates forward movement – think walking and running. The second function, accommodation, is the ability to adjust to the terrain surface and absorb forces from the ground.

Why Should You Spend Some Time on Your Mobility

In a perfect world, you would have at least 2 hours per day to train; your own personal chef, and you would get at least 9 hours of sleep every night. Most tactical athletes don’t have that luxury, so it pays to have an awareness of your recovery and self-care. Taking care of the little things can optimize performance while making consistent deposits in the savings account and support career longevity.  Here are a few reasons to tactically integrate some ankle mobility work into your training session.



Some asymmetry is considered pretty normal, but a number of studies show that an asymmetry of greater than 5 degrees between sides using the weight-bearing ankle dorsiflexion test can increase the risk of overuse injury by 2-4 times compared to those without an asymmetry. On the Knee to Wall Test, this is the equivalent of a little more than a 10% difference side-to-side.


Previous Injury

Time and again, the evidence continues to show the most common risk factor for injury is previous injury. This brings us back to the discussion of asymmetries. It’s not uncommon for previous foot and ankle injuries to resolve but they have persistent mobility deficits. Ankle sprains, one of the most common injuries in the tactical population, are a significant source of residual ankle mobility deficit.


Training Needs

Some training exercises have specific range of motion demands. If these exercises make up a significant part of your training program, then having limited ankle mobility can change the way you move through an exercise. This shifts the loads around your body and may make the exercise less effective or potentially increase your risk for injury. Training is the means to an end, not the end itself, and should build you up to meet your job demands, not keep you away from performing due to injury.


You Need Enough Range of Motion to Get Your Job Done Safely

Most importantly, if your job involves kneeling, crawling, carrying, and running with heavy equipment, loaded with gear or assisting others, you may find yourself in a variety of different positions. Regular maintenance of mobility exercises and repetition of those joint positions in your training helps you ensure you are physically prepared for the most demanding situations. 


Assess Your Own Ankle Mobility

At O2X, we utilize the Knee to Wall Test as part of our readiness assessment to screen tactical athletes for mobility deficits that could increase their risk for injury. Place a ruler on the floor with the zero against a wall. Start with your toes against the wall and your heel flat on the floor. Keep your foot flat, bend your knee, and try to touch your knee to the wall. If you can touch AND keep your heel flat, then back up a little bit. Keep backing up until you can’t touch the wall with your knee, AND keep your heel flat at the same time. Record the distance from the wall in centimeters for the first foot and then compare it to the other side. This should give you a good estimate for any asymmetry. 


Try These 5 Drills to Improve Your Ankle Mobility

Foam Roll – Calf – The classic calf foam roll is a great way to loosen up and relax the tension in your calf muscles. Try this for 30-60 seconds per side. 


Foam Roll – Soleus – To spice it up, you can take on the soleus muscle. Deep to the main calf, it crosses only the ankle joint and can be mobilized in a half kneeling position. Use a dowel, foam roll, mobility stick, or rolling pin to massage the muscle and tendon with your knee over or behind your ankle. Progress by rolling with your knee progressively further over your toes. Notice if the tension changes as you rock forward and back. Try this for 30-60 seconds per side.


Ankle Dorsiflexion with Toe Extension – The flexor muscle under your big toe runs under your foot, behind your ankle, and up the back of your leg. It’s a thin muscle but can limit your ankle mobility. To stretch this muscle, extend your toe against a stair riser and gently rock your knee over your toes. Try 5-10 reps per side. 


Banded Ankle Dorsiflexion – Banded mobility drills help you use the joint anatomy to your advantage. The band blocks the motion of the lower half of the joint allowing the top half to glide more freely. Try 30-60 seconds per side. 


Multidirectional Dorsiflexion – This drill improves ankle joint range of motion in multiple directions. This may be particularly helpful if you’ve had a history of ankle sprains, fractures, or surgeries, particularly with immobilization afterward. This mobility will help movement efficiency in multiple planes of motion and unpredictable environments. Try 30-60 seconds per side. 


*This post is not medical advice. Some discomfort may be noted with different drills, but you should not push yourself to cause pain or injury. If you have pain, consult a medical provider.