If you have Achilles tendonitis, it is very likely that you will experience flare-ups in pain during your rehab. This can be very frustrating and even upsetting. In this article, I’ll share some tips on what treatment works best and how to get through these flare-ups as quickly as possible. Remember, if you need more help with an Achilles injury, you're welcome to consult one of our team via video call.
The terms tendinitis, tendonitis, tendinosis, and tendinopathy mean the same thing for all practical purposes, and we use these interchangeably in our articles.
In this article:
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Pain does not equal damage
It’s normal to think that when something is very painful, it must be badly injured. But this is not the case. Researchers have found that, although pain is often present when something is injured, you can also have pain without being injured or be injured and not feel pain.
The current understanding is that pain is an alarm system that is meant to get you to take action when something goes wrong in your body, but that this alarm system can sometimes malfunction. Things that can make pain feel much worse than what it’s supposed to include your emotions (being very worried or frustrated with an injury), beliefs (being concerned that this injury may be very serious or permanently put an end to your running), or simply being in pain for more than three months.
This has been shown to be true for all parts of the body, but a recent study demonstrated this specifically in the Achilles tendon. A team of researchers analysed 145 patients with Achilles tendinopathy and found that they could categorise them into three groups.
The first group was very active (playing sports), performed well when they were asked to perform the physical strength test (how many calf raises they could do), and did not complain of much pain. When the researchers scanned their tendons, they did not find much structural damage.
The second group reported having lots of pain and being frightened of moving, because they were worried that it would increase their pain or damage their tendons, but they demonstrated fair strength during the calf raise exercise test. Surprisingly, despite their high pain levels, their scans showed very little structural damage in their tendons.
The third group wasn’t very active and fared quite badly on the calf raise exercise test but also did not report much pain and did not feel that their injury impacted them much. Interestingly, this group’s tendons actually showed a lot more damage on scans, compared to the other two groups.
Why flare-ups happen
When we’re injured, the pain receptors in the affected area is usually a bit more sensitive and easier to irritate and even gentle movements can cause them to fire off. The tendon loses some of its capacity to tolerate loads and this is why even normal daily activities can cause pain. If you pitch your rehab exercises at the correct level and apply relative rest, that sensitivity usually decreases over time, and the tolerance increases.
Flare-ups happen when you increase the load on an injured area too quickly, causing the sensitivity to increase. When an injured tendon is in the reactive or very sensitive stage, shortly after the injury, this flare-up response can sometimes be disproportional to the activity, e.g. a slight increase in activity can cause a dramatic increase in pain.
Tendons are also fickle, and they don’t always let you know in the moment that an exercise session is too hard. They often wait a few hours or even until the next day to flare up and become painful.
It’s often not rehab exercises alone that cause a flare-up. Normal daily activities like gardening or walking longer distances can accumulate to cause the increase in symptoms.
Common causes of flare-ups include:
Using a weight that’s too heavy or an exercise band with a resistance that’s too high
Doing too many repetitions or sets of an exercise
Holding stretches for too long or stretching too hard (injured tendons often don’t like being stretched)
A sudden increase in the volume of an activity, e.g. steps per day
A sudden increase in exercise intensity, e.g. fast running sessions or hill running sessions.
Have I made my injury worse?
In most cases, no. If the activity that caused the flare-up was not excessive, and you didn't experience any sudden, sharp pain, you've likely not worsened your injury. Instead, your body simply created some pain and stiffness to warn you to take things easy for a few days.
If you felt a sudden, sharp pain (which may indicate a tear) and/or significantly increased the volume or intensity of your activity, then there's a chance that you may have worsened your injury. A physiotherapist will be able to assess this for you.
What to do in case of a flare-up
When you have a flare-up, you need to take a step back and reduce your activities to allow the flare-up to settle down. If you try and train through it, it will very likely just get worse. It’s a bit like prodding a bruise – the more you do it, the more painful it gets.
This sounds easy, but it can be mentally very hard to take a break from training. However, if you act quickly and allow the flare-up some time to settle down, you’ll likely be able to work back up to your previous level of training within a week or two.
You may not have to rest completely – your physio will be able to guide you on the best course of action. But it’s important to gradually ease back into your training and start with a reduced training load once you’re ready.
Some things that may help your tendon pain calm down sooner:
Wearing a heel lift or shoes with heels to temporarily reduce the strain on the tendon
Low-load exercises, like double-leg heel raises, can often help to relieve the pain by increasing circulation without placing too much strain on the injured tendon.
How we can help
Need more help with your Achilles injury? You’re welcome to consult one of the team at TMA online via video call for an assessment of your injury and a tailored treatment plan.
We're all UK Chartered Physiotherapists with Master’s Degrees related to Sports & Exercise Medicine. But at Treat My Achilles we don't just value qualifications; all of us also have a wealth of experience working with athletes across a broad variety of sports, ranging from recreationally active people to professional athletes. You can meet the team here.
About the Author
Hanlon, S. L., et al. (2021). "Beyond the Diagnosis: Using Patient Characteristics and Domains of Tendon Health to Identify Latent Subgroups of Achilles Tendinopathy." J Orthop Sports Phys Ther 51(9): 440-448.
Rabusin CL, Menz HB, McClelland JA, et al. "Efficacy of heel lifts versus calf muscle eccentric exercise for mid-portion Achilles tendinopathy (HEALTHY): a randomised trial." British Journal of Sports Medicine 2021;55:486-492.