If you’re a runner, there is a good chance you or someone you know has experienced Achilles Tendinopathy. I suffered from this injury a few years ago while I was training for my first marathon. It was not a fun time! It was mainly caused by progressing too quickly during my marathon training and not paying close enough attention to outside forms of stress. For my second marathon, I wasn’t going to let this happen again. I listened to my body, progressed slowly with my training, and did some strength exercises to support my running legs. Shocker, I didn’t get any Achilles pain!

Research tells us that about 50% of runners will suffer from Achilles Tendinopathy during their running life (Knapik & Pope, 2020). That is huge! Furthermore, Achilles Tendinopathy is one of the most common running-related injuries overall alongside medial tibial stress syndrome and plantar fasciitis (Lopes et al., 2012). Even more reason to try to understand what we can do to treat it and/or reduce the risk of having it even though we can never do this at 100%.

What is Achilles Tendinopathy?

Firstly, the Achilles tendon is the longest and most resistant tendon in our body. It’s what connects the calf muscles to the heel bone and its job is to take the load in activities such as walking, running, or jumping. Think about movements or activities that involve the foot having to produce a force with the foot pointed.

Achilles Tendinopathy is essentially an overuse injury to the Achilles tendon and in the case of runners, it is often caused by the excessive load of this tendon (Knapik & Pope, 2020). This injury causes pain, swelling, and morning stiffness. The pain is often made worse with activities that increase the Achilles tendon load such as walking, running, or jumping. Runners can see a decrease in their performance when the pain becomes too much while running.

What are the risk factors for Achilles tendinopathy?

A recent systematic review by Zainuddin et al. (2022) highlighted the factors that could be associated with runners that had Achilles Tendinopathy compared to healthy runners. Some of these factors were:

• Different knee flexion angle, ankle dorsiflexion, ankle eversion, touchdown angle, and plantarflexion moment during the loading phase

• Different ground reaction forces

• Longer duration of eversion and over-pronation

• Difference in muscle activity of the calf muscles during various running phases (tibialis anterior and medial and lateral gastrocnemius)

  We know that these factors are present in people already suffering from Achilles tendinopathy. However, this doesn’t indicate if it’s the cause or the consequence. Although we understand that Achilles tendinopathy is an overuse injury mostly due to increased load, the available evidence is still limited as to what biomechanical factors can cause it.

  A recent prospective study by Skypala et al. (2023) might have some answers for us. When following 108 healthy runners for one (1) year, they found that 37% of males and 25% of females developed Achilles tendinopathy. When comparing the runners that had AT to the ones that didn’t, they found that runners with AT had a more flexed knee at initial contact and the midstance phase and that this was a predictor for developing AT. In other words, having a more bent knee when the foot first hits the ground and at midstance will increase the risk of Achilles tendinopathy. This is important information that can be used to prevent the development of AT in runners.

What are the recommended treatments for runners suffering from Achilles Tendinopathy?

There is no one size fits all and different people can respond better to different approaches. The best way to know what treatment approach is best suited for you is to get an assessment from a physiotherapist or medical professional who specializes in treating runners.

The goal of the treatment for Achilles Tendinopathy is to decrease the load on the tendon. Here are some of the treatment options that can help runners with Achilles Tendinopathy:

1) Strengthening quads and glutes

We know that the quadriceps muscle, as well as the gluteus medius (glute med), are muscles that should be active during the stance phase. If these are doing their job properly this will decrease the load on the calf complex and the Achilles tendon. Below, you can see a graphic showing the glute med that is properly activating (A) and one that is not (B). In picture B we can see that this causes a hip drop on the opposite side as well as more pronation of the foot (collapsing in) and more hip adduction (femur going towards midline). All of this increases the load on the Achilles tendon.

Image source: Magee, David J. Orthopedic Physical Assessment. Philadelphia :Saunders, 2008. p.681

2) Progressive loading of the Achilles tendon

When the pain is intense, some people will even have trouble tolerating pointing the foot. Others will have pain with walking and some will have pain after 5 km of running. Everyone presents a little differently and has different levels of fitness. Progressive loading means increasing the load to the tendon little by little and taking into account what it can tolerate. For example, this can look like heel lifts from a flat surface starting with 2 feet, then progressing to 1 foot, and then progressing to heel lifts from a step with 2 feet and then 1 foot.

3) Adapting the shoes and heel lifts

What kind of shoes are you currently using? Having the heel a little bit elevated can decrease the load on the Achilles tendon. This is something to consider when you are suffering from this type of injury. It doesn’t mean you need to change your shoes forever, but this might help reduce your symptoms if you choose a shoe that has a bit more drop (the difference between the front and the back of the shoe). Another option is to add a heel lift in your shoes which has the same goal as increasing the drop. These can comfortably be inserted in your shoe and won’t break the bank.

4) Changing your training parameters

There are a few things that can be tweaked in a training plan to reduce the load on the Achilles tendon:

• Reduce volume (less distance or time ran in your week)

• Reduce frequency (run fewer times in your week, ideally every other day or less)

• Reduce intensity (run more low-intensity runs and less threshold or high-intensity runs) Do the 80 part of the 80/20 rule

• Take out or reduce hill training for now

To sum up, Achilles Tendinopathy is very common in runners, but it doesn’t mean that it is normal. We should not ignore it when it arises and seek help if it is getting worse or lingering. A lot of times runners are afraid to seek help because they don’t want to be told to stop running. The good news is, most of the time, you can continue running as long as the training plan is modified and adapted to your specific needs.

Happy running,

April

References:

1. Knapik, J. J., & Pope, R. (2020). Achilles Tendinopathy: Pathophysiology, Epidemiology, Diagnosis, Treatment, Prevention, and Screening. Journal of special operations medicine : a peer reviewed journal for SOF medical professionals, 20(1), 125–140. https://doi.org/10.55460/QXTX-A72P

2. Lopes, A. D., Hespanhol Júnior, L. C., Yeung, S. S., & Costa, L. O. (2012). What are the main running-related musculoskeletal injuries? A Systematic Review. Sports medicine (Auckland, N.Z.), 42(10), 891–905. https://doi.org/10.1007/BF03262301

3. Skypala, J., Hamill, J., Sebera, M., Elavsky, S., Monte, A., & Jandacka, D. (2023). Running-Related Achilles Tendon Injury: A Prospective Biomechanical Study in Recreational Runners. Journal of Applied Biomechanics, 39(4), 237-245. Retrieved Jan 26, 2024, from https://doi.org/10.1123/jab.2022-0221

4. Zainuddin, F.L., Abd Rahman, N.A., Razman, R. et al. (2022) Lower limb biomechanical factors associated with Achilles tendinopathy in runners: a systematic review. Sport Sci Health 18, 27–38. https://doi.org/10.1007/s11332-021-00862-4