Why Does My Achilles Tendon Hurt When I Run?



Are you starting to feel soreness in the back of your ankle with running? Does it feel stiff when you wake up in the morning or at the start of your run? Are you wondering, why does my achilles tendon hurt when I run?



In this episode I cover all of the myths and provide you with the latest research on what Achilles Tendonitis is and how you don’t need to stop running to overcome this very common running injury! 


This is Part 1 of this topic where I will go over exactly what Achilles Tendonitis is. Next week in Part 2, I will discuss the treatment and prevention of this injury! 



Click below to see the live video from our Healthy Runner Facebook Group…

Listen to the Podcast Episode during your next run!


This week I answer the most common questions about this condition including : 

  • What is Achilles Tendonitis
  • What causes Achilles Tendonitis
  • What are the symptoms of Achilles?
  • Do I need an MRI to diagnose Achilles Tendonitis?
  • What would a medical provider do on exam?

Let’s get into it with the blog!


1. What is Achilles Tendonitis?


Achilles Tendonitis is a very common condition among runners where they start to experience some pain in the tendon that runs along the back of the leg and into the ankle. Remember that “-itis” means inflammation, so there’s inflammation occurring in this tendon!




This is the largest tendon in the body. It runs from the bottom of your calf muscle, all the way to your heel bone where it inserts! When you walk, run, climb stairs, and stand on your tip toes, you’re using this tendon! The Achilles Tendon is very strong and can withstand great stresses. However, the tendon can also be prone to overuse and degeneration issues which leads to this pathology of Achilles Tendonitis.


The tendon can become irritated and inflamed which then causes pain. An individual with Achilles Tendonitis may notice pain in the mid-portion of the tendon, about 2 inches above the heel bone or there may be pain where the tendon inserts at the heel bone.


2. What Causes Achilles Tendonitis?


Achilles Tendonitis occurs from repetitive stress to the tendon. As stated previously, the Achilles Tendon can handle a lot of stress – but when too much is done too soon, or too much load is placed on the tendon over and over, it can become irritated.


Other risk factors that may lead to Achilles Tendonitis include:


  • Improper Training Progression with a rapid increase in speed, mileage and uphill running.
  • Tight calf muscles can can pull too much and put extra stress on the Achilles.
  • You may have an extra bone growth where the Achilles Tendon attach on the heel. This is called a Bone Spur and it can cause inflammation and pain.
  • Decreased total lower extremity strength can lead to higher stresses on the Achilles due to compensations. Strength work is KEY for this reason! Activation of shin, thigh, calf, and hip muscles (especially those glutes) is going to be super important!
  • Rapid change in footwear with less shock absorption or with a heel drop can lead to added stress on the Achilles.
  • Being a Forefoot Striker. Running on your toes can lead to increased stressors on your Achilles.


3. What are the Symptoms of Achilles Tendonitis?


There are MANY different symptoms associated with Achilles Tendonitis. Some of the most common symptoms include:


  • Pain and stiffness along the Achilles Tendon in the morning
  • Pain along the tendon or back of the heel that worsens with activity
  • Severe pain in the Achilles area the day after exercises
  • Thickening of the tendon
  • Bone Spurs
  • Swelling that is present all the time and gets worse with activity




Hearing or feeling a “POP” in this area is a much more significant injury. The pop, or feeling of being shot in the back of the heel, is an Achilles Tendon Rupture (or torn Achilles). See your doctor immediately if you think you may have torn your tendon.




4. How is Achilles Tendonitis Diagnosed?


A medical provider will look for the following signs during an exam to determine if an individual has Achilles Tendonitis…


  • Swelling along the tendon or the back of the heel
  • Thickening or enlargement of the Achilles Tendon
  • Bony spurs at the lower part of the tendon at the back of the heel (this is insertional tendonitis)
  • Point tenderness on the tendon
  • Pain in the middle of the tendon
  • Pain at the back of the heel
  • Limited Range of Motion in the ankle – specifically decreased ability to flex your foot
  • Strength Assessment
  • Heel Raises that increase pain


In next weeks episode we will discuss treatment and prevention of this pathology… stay tuned and subscribe to our YouTube Channel and Podcast so you can stay in the loop!!


In the video version of this episode, I also mentioned our brand new high touch coaching program…

SPARK Back Coaching Program.  To learn more about this program click this link to jump on a 30 min strategy phone call: https://calendly.com/duanescotticoaching/30-minute-strategy-session


This episode, our 60th episode (can you believe it?!) is sponsored by UCAN energy! UCAN nutrition is powered by superstarch and it delivers that steady long lasting energy without the spike and then the crash.


Since you are part of our healthy runner community, you will get 15% off all of your orders at ucan.co.  Just use the code HEALTHYRUNNER during checkout when placing your order.  Go ahead and give ucan a try, trust me…you won’t regret it



You can listen to all the information in this episode on the Healthy Runner Podcast…available wherever you get your podcasts!



Here is what other runners are saying about the podcast



Thank you (running friends) for taking the time to read and I hope you enjoy the podcast episode!

Warmest regards,


– Duane


Duane Scotti, PT, DPT, PhD, OCS



⚡️ SPARK Physical Therapy and the Healthy Runner Podcast  Helping Active Adults Be Able To Run Without Aches and Pains So You Can Feel Good About Yourself Again…

[Even If You Don’t Think You Are A Runner]

If you are a runner and frustrated with your nagging aches and pains and have been told to stop running, we can help you.


Health for Runners BY Runners ‍


Related posts

Is It Ok To Run with Hamstring Pain? | Hamstring Injury Exercises

Do you get that stubborn pain at the top of your hamstring right where it connects to your “sit bone” and you are wondering if it is ok to run with hamstring pain? This could be a dull achy pain that gets worse after your runs or sitting for a long period of time during… View ArticleRead More

5k and Half Marathon | 3 Can’t Miss Tips

Do you know what the best way to prepare for a half marathon is? Do you know what you should do before a 5k? This week’s Healthy Runner Podcast answers those questions for you!   In episode 29, I had the pleasure of talking with running coach Cat Aniballi! She is so passionate about running… View ArticleRead More

What Should I Eat and Drink During Long Runs

  Should runners diet to lose weight?  Find out from our sports nutrition expert!   In this episode,  We have Jenn Giles from Eat 4 Sport on the show to educate us on what food we should be eating and when we should eat those foods to not only lose weight but run at our… View ArticleRead More

“I developed IT band syndrome during my first marathon training cycle last year and ended up in physical therapy for about 3 months. I was told not to run if I had any pain at all. I lost so much time “recovering” that I ended up deferring my registration to the next year. I spent the next summer training for the same marathon when about 6 weeks out, that familiar IT band pain returned. I could barely finish a mile. I didn’t want to go back to my physical therapist because I knew what he was going to tell me. Stop running. I was so frustrated and started to feel like marathons weren’t for me. I stumbled upon the healthy runner podcast and learned that I don’t have to stop running in order to recover from injury! I was skeptical about an online physical therapy session. But I reached out to Dr. Scotti and he was able to give me the tools to mitigate my pain within the first session! I was able to complete my training cycle and made it to the finish line of my first marathon with his help! I highly recommend!”

Kendyl R. (Runner)

“I’d been dealing with Proximal Hamstring Tendinopathy (PHT) for about 4 years and had been doing PT, but still had lingering pains. I just figured I’d have to suck it up and deal with it because that was as good as I was going to get. But then, I came across a podcast of Duane being interviewed by Jason Fitzgerald on PHT and how he overcame the injury, and my curiosity was piqued. I met with him virtually and he has been a GODSEND! I’m able to sit as I type this! I can bend over and get in and out of cars without pain! And, I’m RUNNING again!!! It is amazing to be able to do things that I haven’t been able to do without pain since 2016!!! Thank you so much Duane for being an incredible PT!!”

Michelle D. (Runner)

“I suffered from IT band syndrome for four years before seeing Dr. Scotti in April 2020. Before then, I couldn’t run more than about 10 minutes without stabbing pain near my left knee. I’d seen various orthopedists, physical therapists, and chiropractors looking for some relief. My career needed me to run a mile and a half within a certain amount of time, and it was impossible to do so with the knee pain. I saw Dr. Scotti and he immediately got to work! That first visit, he helped me understand the anatomy and underlying cause of my knee pain (aka IT Band syndrome). Once I understood what was happening, the course of treatment made so much sense. Not only did he have online videos of all the recommended exercises to treat the problem, his “healthy runner” Facebook group, Podcast, and YouTube videos held a wealth of information and supplemented my plan. I soon understood that running wasn’t just a casual hobby – it’s a sport and one that deserves dedication and focus. Without his dedication to the sport and his community, I wouldn’t have realized this! Over the next few months, I had many ups and downs – victories and failures – and even some tears! Two steps forward and one step back. Dr. Scotti always checked in between appointments and tweaked my plan if needed. By August, I was regularly running 3-4 miles with barely any pain! If I did get pain, it was because my dedication and focus were lacking – and I quickly picked it back up and overcame. I’m so thankful I took another chance at having my knee looked at and trusted someone else. I run regularly now and am really enjoying it. I can’t thank Dr. Scotti enough and would highly recommend him to anyone having trouble.”

Tracy G. (Runner)

Sign up for our weekly blog and podcast in order to help you stay active, healthy and just keep running!