Build Stronger Ankles For Better Trail Running

Ankle injuries are common in trail running, here’s how to prevent them

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Strong, healthy ankles are crucial for trail running. Not only do they absorb impact and help propel an athlete forward, but they also serve a crucial role in the stability and coordination of an athlete. Because the ankle carries the majority of the human weight above it and is more narrow in build, it is also at a higher risk of injury. For that reason, ankle strength and mobility are significant when it comes to effective trail running.

Here are the most common ankle injuries trail runners can experience and tips on how to prevent them.

Common ankle injuries and who is at risk

According to Dr. Katie Carbiener, physical therapist and running coach with Carbs Performance Wellness in Golden, Colorado, while the most frequent ankle-specific injuries she sees in her practice are sprains, Achilles issues, and posterior tibial tendon dysfunction (PTTD), she also deals with many foot, knee, and hip injuries that stem from poor strength and mobility in the ankle.

Ankle Sprains

An ankle sprain occurs when the ankle experiences an abnormal movement that causes the ligaments to stretch or partially/ fully tear. Sprains are classified into three grades, which dictate how the athlete should work on healing and time their return to activity.

Grade one sprains are when there is stretching and mild damage to the soft-tissue fibers of the ankle. A grade one sprain presents with mild swelling and tenderness and does not require any splinting or aid aside from optional icing. With a grade one sprain, an athlete can return to activity within a day or two as long as the pain has subsided.

Grade two sprains are more severe, with complete tears of some fibers and partial ligament damage. This classification of sprain is identified with more swelling and a limited range of mobility. The pain is more prevalent, and the balance on that leg feels somewhat altered. The athlete might need to use an air splint early in the recovery process and integrate mobility and strength training as they prepare to return to running.

Grade three sprains are the most severe, occurring when a ligament fully tears or ruptures. Grade two and three sprains can appear similar but will have more severe pain and swelling and almost no stability on the injured leg. In less severe cases, the return to activity will take a little longer and require more time working on strength and mobility before a full return. In the most aggressive scenarios, the ankle might require reconstructive surgery.

RELATED: Bounce Back Faster After An Ankle Sprain

Recurring Sprains

Many runners have experienced the phenomenon of having a reoccurring sprain in an ankle. According to Dr. Carbiener, the ligaments in the ankle not only stabilize the ankle but help the body understand where it is in space. An injury to the fibers of the ankle causes instability and weakness, increasing the odds of sustaining another injury.

“After an injury, some people rest too much; it is important to get blood flow back to the area,” she says. “Along with compression to minimize the swelling, start engaging in non-painful strength and walking as soon as possible. If someone rests too long, their likelihood of re-spraining the ankle increases. When you return to running, stay on flat, non-technical surfaces.”

Post Tibial Tendon Dysfunction (PTTD)

The post tibial tendon connects the calf muscles to the bones on the inside of the foot. Its main role is to help stabilize the runner as well as support the arch. PTTD is an irritation of the tendon that can be caused by trauma (such as a fall or a twist) or from overuse. Chronic inflammation or damage to this tendon can eventually lead to lasting arch issues or collapse.

With PTTD, the athlete will need to lower their mileage immediately and start a strength and stretching regime targeted at the feet and calves.

Weak Ankles are a Pain All Over

Ankle weakness or lack of mobility can lead to foot, knee, or hip pain. Tight, immobile ankles can play tug-of-war with the rest of the body, causing tension in the feet and calves, which gradually causes the knee and hip to not function correctly. 

Tight or weak ankles can also limit dorsiflexion (or the movement of the toes toward the ankle, crucial in the swing of a runner’s stride) which significantly limits the gate and power in each step, as well as being linked to increased risk of plantar fasciitis or ACL injuries

Who is at risk of ankle injuries

While trips and slips can be sustained by even the most seasoned runner, ankle strength and practiced stability will lessen the likelihood of surprise sprains. Those returning to running, especially after sustaining a previous ankle injury, are at a higher risk of re-injuring the area.

Mobility can also be a cause for injury. Dr. Carbiener also states, “Hypermobile athletes have a higher injury rate since they do not have the same stability. However, a stiff foot and ankle can have trouble reacting on the trail. Either end of the spectrum of tightness is not ideal, a runner wants to be in the middle.”

RELATED: 2 Ankle Mobility Exercises You Should Be Doing for Injury Prevention

How to Prevent Injury and Gain Power

While ankle injuries are common, they are also easily preventable. By incorporating daily strength and mobility practices, improving form, working on balance and coordination, and finding the right footwear, ankle injuries can be mitigated, and full power can be restored to the stride.

Exercises for unstable ankles

Strength and mobility are some of the easiest places to start. Hillary Osborne, a NSCA personal trainer and ultrarunning coach with Blaze Strength and Endurance in Lakewood, Colorado, explains, “The foot may be the first point of contact, but the ankle is the connector of the big toe to the calf. As long as there is strength and mobility, we can control the ankle and all of its movements. Without that control, we run the risk of injury.”

Foot alphabet

The foot alphabet can be practiced while at work or hanging out at home. With one leg elevated in the air, spell the alphabet in the air with your toes. This exercise works four major muscles in the calf, which helps improve stability (limiting sprains, strains, and rolls) as well as building the muscles stronger and preventing any overuse injuries. While this exercise might sound easy, the concentrated movements could be difficult to begin. Start by doing this exercise once or twice daily with each foot.

Eccentric Calf Raises

Calf raises of any variety are great because they engage muscles in both the foot and the calves. For this exercise, it is best to stand on a stool, box, or step so that the balls of the feet are planted, and the heels hang down. Slowly lower the heel as far as it will go with the toes staying on the step, hold for a moment, then raise until standing on tippy-toes. Repeating this slowly, moving to practice with one leg at a time, and then adding weight will engage and strengthen muscle groups while also building mobility in the ankle needed for durability and power. When adding weight, start small, with five pounds, gradually increasing as the strength builds.

Resistance Band Inversion and Eversion Movements

Resistance bands are a great way to target the ankle specifically for direct strength and mobility work. To start this exercise, take a resistance band and hook it on a stable object at ground level. For inversion, start with the exercise band on the same side of the body as the ankle that is being worked. Hook the resistance band around the foot and slowly move the foot from pointing out to about 45 degrees pointing in. For eversion, the band will go across the body, and the movement will go from pointing the foot in to pointing out.

RELATED: Ankle Taping For Trail Runners To Prevent Ankle Injury

Deep Soleus Kneeling Stretch

Creating mobility in the calf, foot, and ankle is all necessary for lasting ankle health. Kneel with one leg behind, the top of the foot pressing into the floor. Move the other foot so the ankle is parallel with the knee. Move hands to the ground and press forward while ensuring the planted foot stays completely rooted, with the heel not leaving the earth. “Hold this stretch longer than you think is necessary,” Dr. Carbeiner recommends. “One to five minutes on each side is ideal to create lasting change in the muscle fibers.”

Working on balance and coordination

Rocky trails require stability, which is a project for the entire body. Certified personal trainer and body balance coach Becca Jay, of Get Up! Training in Littleton, Colorado, explains, “Balance starts with the question, ‘can you figure out where your body is in space?’ This can be done with single-leg or closed-eye exercises. Balance connects people with their bodies, but injuries, trauma, and stress all make it hard to be aware of where the body is.”

Creating more balance in the body can be done with both dynamic as well as static exercises. Static balance exercises, or practices of holding a single balance position, help increase the mind-body connection and create a better understanding of where the body is in space. Dynamic balance works to create more eccentric (lengthening) contractions and help develop stronger muscle fibers in the ankles and feet, as well as engage the larger above muscles, such as the gluteus group and abdominals. Dynamic balance can be done with single-leg hops both back and forth and lateral, activities on the bosu ball or focused yoga practice.

When working on balance, Jay recommends, “Notice where you are without judgment. Don’t beat yourself up if balance does not come easy. The human body does not come out symmetrical. Pay attention and do what you can to support your body to be durable.”

Adjusting form

Pronation, or the inward movement of the foot while running, is a natural part of a running stride. However, overpronation occurs when the inward roll of the foot becomes excessive, flattening out the arch. Over time, overpronation can lead to lasting foot, ankle, knee, or hip pain that is difficult to correct. Making time to see a running gait specialist and ensuring that ankle pain is not coming from a running mechanics issue can save from lasting injury.


Sometimes, changing out a pair of shoes can make the biggest difference in injury prevention. It is worth taking the time to ensure that shoes fit correctly, are not overly worn in places and are properly addressing the runner’s needs.

Wider toe boxes

The big toe is a major player in running form. It is the last point of contact during the gait cycle, and plays a key role in stabilizing the foot in a single-leg stance so the runner can begin the toe-off phase that leads to the next stride. When a slightly or overly narrow toe box of a shoe causes the big toe to get pressed too tightly (or doesn’t allow toes to appropriately splay out), the foot loses its propulsive power, and the ankle becomes limited. “If the toes are tight, the range of motion is limited,” Obsorne says. While too much room in the shoe can result in a sloppy feeling that could cause the foot sliding inside the shoe and banged-up toenails, having a little bit of extra width can make a huge difference for optimal stability and propulsive toe-off.

RELATED: The Evolution of Trail Running Shoes

Supportive arch

Correct arch support is also important for ankle health. Because the arch connects to the calf through the ankle, a tight or inflamed foot can lead to pulling and discomfort in the ankle. It is important to change out shoes before they break down and to take time to ensure the arch is in the correct part of the foot.

While ankles are resilient, an injury can be lasting and significantly affect a person’s ability to get out and enjoy the trials. By incorporating strength, mobility, and balance into an exercise regime, as well as ensuring that form and shoes are correct, a runner can work to prevent injury and create healthy longevity in the sport.

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