Why Your Achilles Tendon Rehab is Failing: Key Missteps and How to Fix Them
Achilles tendon injuries are among the most common injuries in runners, especially in the Masters population.
They also happen to be among the most feared.
We’ve all heard stories of nagging, debilitating, recurring pain that derailed running goals for months or years on end and was resilient to one rehab effort after another.
But it doesn’t have to be that way!
Yes, Achilles tendon injuries are common, especially among Masters runners, and rehab can be incredibly frustrating. But a big part of that frustration usually stems from misguided attempts at rehab.
While rest, ice, and passive treatments might seem like the best approach, they often fail to achieve lasting recovery.
Here are some of the most common reasons rehab efforts fall short and how to address them.
1. The Approach Is Too Passive
One of the biggest mistakes in Achilles tendon rehab is relying too heavily on passive treatments like ice, massage, and rest.
While these methods can provide temporary relief, they do little to promote actual healing or improve the tendon's strength and resilience. Tendons respond to load, meaning they need to be progressively stressed in a controlled way to adapt and become stronger, increasing their tolerance to stress.
2. Loads Aren’t Appropriately Progressed
While bodyweight exercises like calf raises are a good starting point, they only take you so far. The Achilles tendon must withstand higher stress levels, particularly when the goal is to happily return to running, where the tendon is under significant load during each stride.
To build a tendon that can handle the forces of running—where it may absorb up to 4-8 times your body weight with every step, multiplied by thousands of steps each run—you need to load the tendon progressively.
Add load with weights.
Slow a movement down to add challenge.
Failure to continue to progress as you move through the rehab process is a fast track to symptom recurrence.
3. The Soleus Is Often Overlooked
The calf complex, composed of the gastrocnemius and soleus muscles, is integral to Achilles tendon function. However, the soleus is often neglected in rehab programs. The soleus is a powerful muscle with a larger cross-sectional area than the gastrocnemius and plays a key role in force production, especially when the knee is bent.
Targeting both muscles when performing calf exercises is essential for a well-rounded rehab program. Bending the knee during calf raises or other calf exercises specifically engages the soleus, which can absorb and generate forces up to 6-7 times your body weight as you run. Ignoring this muscle can leave a gap in your rehab, preventing the tendon from adapting fully.
4. Overemphasis on Footwear
Footwear is a common focus in Achilles tendon rehab, and for a good reason—shoes with a slightly elevated heel-toe drop can reduce the load on the Achilles tendon. In contrast, shoes with a lower drop will increase your ask on the Achilles.
However, it is a mistake to rely too heavily on footwear without addressing the tendon's underlying capacity. Footwear might provide temporary relief but does not solve the root issue: the tendon’s ability to withstand and adapt to stress.
A good shoe might help in the short term, but strengthening the tendon through progressive loading and targeted exercises is essential for long-term recovery. You need to prepare the tendon to tolerate the load, not just use a shoe to reduce it.
5. Introducing Plyometrics Too Early
Your Achilles tendon functions as a giant spring in your body. With every step you take, it stores and releases “free” elastic energy to drive you forward. If you use that spring well, it is estimated that it can account for up to half the mechanical cost of running.
It makes sense, then, that part of rehabbing an Achilles injury is ensuring that you’ve dialled in that spring mechanism.
However, these exercises should not be introduced too early in the rehab process. Plyometrics require quick deceleration to absorb loads and rapid acceleration to push off the ground, which is a big ask for a tendon that is not yet strong enough to handle these intense demands.
Introducing plyometrics too early can overload the tendon. Before introducing them, be sure that you have progressed well to tolerate greater loads and the introduction of rapid deceleration followed by a quick force production.
6. Not Doing Plyometrics Properly
Even when plyometrics are introduced, they need to be done correctly. Plyometric exercises aim to utilize the stretch-shortening cycle—the tendon’s ability to quickly stretch and recoil like a spring.
For this to happen, the ground contact time must be brief. If you spend too much time on the ground, the load shifts from the Achilles tendon to the knee and quadriceps, defeating the purpose of training the tendon specifically.
To maximize the benefits of plyometrics for the Achilles tendon, you need to focus on short ground contact times. The faster you get off the ground, the better you will engage the tendon and improve its spring-like function. Properly executed plyometrics train the tendon to quickly absorb and release energy, which is crucial for running well, staying healthy and performing your best.
7. Neglecting the role of the brain and nervous system
To successfully perform a task involving a muscle-tendon unit, there are two key requirements:
Sufficient muscle capacity, or strength, to perform the task
Ability to control the muscles when performing the task.
Most rehab protocols nail the first one, focusing on building strength in the calf complex.
The trickier thing to address is the second component, motor control.
When the Achilles tendon is injured, especially in chronic injuries, we see a loss of motor control. This is primarily driven by changes in excitability and inhibition of neural pathways controlling the muscle, as well as belief systems about pain and other contextual factors.
One of the best-supported strategies for improving motor control after a tendon injury is external pacing.
Most strength-based rehab protocols encourage athletes to build muscle capacity by doing a given number of repetitions of an exercise at whatever pace feels best or internal pacing. This builds muscle capacity but fails to address the motor control piece.
Instead, researchers have demonstrated that when we introduce a metronome and encourage the athlete to pace themselves with it, that external pacing strategy increases overall strength while also improving motor control and muscle recruitment. In cases where an external focus was applied, athletes demonstrated significantly reduced pain and symptom recurrence and improved strength and muscle architecture.
So, in cases of stubborn tendons, it is essential to consider whether and how motor control is being addressed in the process.
8. Not Understanding the Demands of Running
Running places unique and demanding stress on the Achilles tendon. It’s not just about enduring a steady load—running involves rapid deceleration as your foot strikes the ground, followed by a quick acceleration to propel your body forward. To rehab the Achilles tendon effectively, you need to understand the specific demands of running and reverse-engineer a rehab plan that targets those run-specific demands.
Building strength and resilience in the tendon requires exercises that mimic the forces and movements of running. This includes plyometrics, eccentric loading, and single-leg work to simulate the stresses placed on the tendon during each stride.
A solid understanding of these demands allows you to work backward and create a rehab program that progresses safely from basic exercises to the complex movements involved in running. While we may be a little biased, finding a rehab professional with a strong background in running is key to long-term success here.
Conclusion
An Achilles tendon injury is among runners' most feared injuries, as they have a reputation for being particularly persistent. However, understanding the biomechanics and demands on the tendon can help create a more effective recovery plan.
Progressive loading, targeted exercises, a focus on the soleus and plyometrics, and a careful understanding of running mechanics are all key components of a successful rehab strategy.
If you are dealing with an Achilles injury, ditch the passive treatments and focus on building your tendon’s capacity to withstand and adapt to load over time. Only then will you be able to return to full activity without risking re-injury.
And, of course, we’re always here to support. Reach out, send questions, and pop into our clinics in Toronto or Hamilton. Know that we’re always rooting for you!