What Is Achilles Tendonitis?
If you have an Achilles tendon ache at the back of your heel that warms up during activity, then bites afterwards, or stiffness first thing in the morning, you are not alone. The good news is that most people improve when they receive structured, evidence-based care for Achilles tendonitis.
Achilles tendonitis is a common overuse injury that causes inflammation, discomfort, and stiffness at the back of the heel, where the calf muscles connect via the Achilles tendon. It often affects active people, especially runners, due to rapid increases in their activity levels. Symptoms of Achilles tendinitis include soreness, swelling and morning stiffness.
The term Achilles tendon tendinitis is often used interchangeably with Achilles tendinitis, although many cases are better described as Achilles tendinopathy, overload and degeneration rather than pure Achilles inflammation. It is also referred to as tendinopathy.
Where Does Achilles Pain Occur?
Achilles pain typically occurs either in the mid-portion of the Achilles (a few centimetres above your heel) or at the Achilles tendon insertion, where it attaches to the heel bone. The Achilles is vulnerable in both locations. Mid-portion Achilles pain is often a load-related problem, whereas insertional Achilles pain may be aggravated by footwear compression on the Achilles and uphill walking.
In general, mid-portion issues are more common in active runners and field-sport athletes, while insertional Achilles irritation can affect a wider age range. It may also be influenced by heel bone irritation, calcification, or a bony prominence at the back of your heel that repeatedly rubs against shoes. A clear location of the pain is the key to planning Achilles tendinitis treatment and pain relief, and to progressing loading. What is important is the pattern of symptoms, where the pain occurs, what aggravates it, and how the Achilles responds to rest.
Achilles Tendinitis Pain Causes
The most common causes of Achilles tendinitis are training errors, calf weakness, limited ankle mobility and footwear choices that place excess load on the Achilles. In most cases, Achilles tendinitis develops when stress on the Achilles exceeds the capacity of the tendon to adapt, particularly after a sudden increase in running distance, speed, hills, or plyometrics (‘jump training’).
Other contributors include:
- Tight calf muscles or limited ankle dorsiflexion
- Poor hip control and altered lower limb mechanics
- Excessive pronation or a very stiff, high-arched foot and ankle
- Worn shoes or a sudden change to lower-drop footwear
- Work that involves prolonged standing and walking
- A history of Achilles tendinopathy or a recent return to sports
Achilles tendinitis is more likely with increasing age, among individuals who carry extra load through the lower limb, and among those who train in ‘bursts’ (e.g., pushing hard on weekends after a sedentary week). Certain medical conditions can increase the risk of tendinopathy, and some medicines can increase the risk in some people.
Often, it is a combination of factors, including overtraining, weak calf muscles, and poor footwear. If your Achilles tendinitis flares soon after a medication change or illness, mention this during your assessment with a medical professional. Treatment should begin promptly to prevent the condition from becoming chronic.
Symptoms of Achilles Tendonitis
Achilles tendinitis typically presents with pain, stiffness, and tenderness that worsen with loading on the Achilles and improve with rest. The Achilles tendon is the largest tendon in the body, connecting your calf muscles to the heel bone. When symptoms develop, the Achilles may feel thickened or sore. Common features include:
- Pain at the back of your heel during running, climbing stairs or doing raises
- Morning stiffness or stiffness after rest
- Tenderness when pressing on the Achilles
- Swelling of the Achilles or thickening, sometimes with a creaky sensation
- Reduced push-off strength or fatigue in your calf
- Flare-ups after activity or the next day
If you experience sudden, severe pain, a pop sensation, rapid swelling, or are unable to push off with your foot, seek urgent assessment for a possible Achilles tendon rupture, as the Achilles tendon may have torn. The Achilles can tear suddenly under excessive load.
Seek specialist attention promptly, also if the pain wakes you at night, if you have swelling in the calf, if you notice a visible change after an injury, or if irritation worsens despite sensible rest.
What Does Achilles Swelling Mean?
Achilles swelling indicates that the Achilles tendon is irritated and struggling with loading, and it often correlates with reduced tolerance for training. Early on, swelling may be mild and fluctuate, leading many people to dismiss it prematurely. However, with ongoing overload, tendon thickening can become more persistent.
Podiatric management for Achilles swelling focuses not on aggressive reduction but on reducing Achilles irritation through targeted load adjustments, then rebuilding capacity to prevent adverse reactions. Achilles tendinopathy with persistent swelling requires treatment that addresses the root cause of the overload.
Is Bilateral Achilles Tendonitis Different?
Bilateral Achilles tendinitis refers to involvement of both sides, often due to changes in training or footwear, calf weakness, or systemic load factors. It can also occur when you dramatically increase your walking volume on weekends, followed by weekday runs.
As both sides are affected, bilateral Achilles tendinitis requires careful load planning and footwear review to avoid offloading one side and overloading the other. Physical therapy and progressive calf loading are essential for bilateral cases.
Acute vs Chronic Achilles Tendonitis
Chronic Achilles tendinitis denotes pain and discomfort that have persisted for more than a few months, with recurrent flare-ups and reduced confidence in the tendon. The Achilles tendon is susceptible to persistent symptoms, including stiffness, tenderness, and reluctance to bear weight. It remains manageable, but it often requires a more structured, progressive plan and closer attention to mechanics.
For chronic Achilles tendinitis, success comes from identifying why the Achilles repeatedly becomes irritated and correcting the underlying cause over time. Clinically, ongoing overload can progress to Achilles tendinopathy (sometimes described as ‘tendinosis’), in which the Achilles becomes less tolerant, more sensitive, and slower to resolve. In plain terms, the longer you ‘push through’, the higher the risk of recurring pain and, in some cases, the risk of partial tearing or rupture of the tendon. This is why seeking care quickly leads to better recovery journeys.
Achilles Tendonitis Management and Pain Relief
A visit to a foot specialist, like a podiatrist, helps identify what’s causing your Achilles tendon to be overworked and suggests ways to reduce strain effectively. For active people in Singapore, including runners, common causes can be small changes in how you run (cadence), tired hip muscles, stiff ankles, or the wrong shoes.
Podiatry treatment for Achilles pain focuses on managing the amount of stress (load) on the tendon, improving how you move (mechanics), and strengthening the area progressively. It’s important to start treatment early and stick with it, as Achilles injuries often recur.
Successful management usually combines physical therapy with:
- Temporarily cutting back on activities that cause a lot of pain.
- Maintaining fitness with gentle options such as swimming or cycling.
- Gradually build up the strength of your calf muscles.
- Sorting out problems with your shoes, movement, and flexibility.
At The Foot Practice, we often use the following methods to treat your Achilles pain:
- RehaWalk® analysis, which uses a pressure sensor treadmill to map how your foot lands and tracks your improvement.
- Footwear Assessments to identify features that put extra strain on your tendons, such as worn-out soles or shoes with very little heel height difference.
- Mobilisation and exercises to restore normal ankle and foot movement, which changes the load on the tendon.
- Custom shoe inserts (orthoses) may be indicated if your foot mechanics and pressure points require specific support.
- Shockwave Therapy (using sound waves to encourage healing) for persistent problems, such as ongoing pain in the middle part of the tendon (tendinopathy). This is always part of a bigger treatment plan, not a standalone fix.
To feel better every day when you have Achilles tendinitis, we focus on ways to reduce the strain on your Achilles tendon without making it weaker. To help your Achilles heal, consider temporarily using heel inserts in your shoes, making smart changes to your gait, and doing strengthening exercises that gradually increase in difficulty as your condition improves.
If the pain is significantly limiting your ability to move comfortably, taking over-the-counter anti-inflammatory medication may help some people for a short time. But remember, these are not the full solution and aren’t right for everyone. A good recovery plan helps your tendon handle normal activity, not just mask the pain while you continue to injure it.
When Imaging Is Useful
Many cases of Achilles tendinitis are diagnosed clinically without imaging. X-rays of the ankle can help identify bony changes near the heel, such as spurs or calcifications, which may be relevant in insertional Achilles tendon cases. X-rays can reveal changes in the tendon attachment. In some situations, additional X-rays may also be requested.
- Ultrasounds can evaluate the tendon in the affected area for thickening and structural changes and are useful for dynamic assessment.
- MRIs may be used for complex cases, such as suspected partial tearing of the Achilles tendon, or when another diagnosis is being considered.
- CTs may be used to assess bony detail in selected situations, although they are less commonly indicated for straightforward Achilles tendinitis.
In some cases, combining X-rays with ultrasound provides the clearest view of Achilles tendon conditions.
Achilles Healing Time
The time to heal the Achilles tendon depends on how long the issue has been present, how inflamed the tendon is, and how well your plan aligns with biology. The Achilles tendon is a structure that responds to loading, and damage in the early stages can often be reversed. Many mild cases improve within 6 to 12 weeks with consistent load management. Longer-standing cases of Achilles tendinitis can take several months to resolve.
The fastest cure for Achilles tendonitis is not a shortcut, as the tendon dislikes them. Rapid pain reduction and healing are possible by stopping aggravation and beginning proper loading early.
Practical Steps You Can Start Today
Adjust load, not movement entirely
If the pain is reactive, reduce hills, speed and long runs. Keep walking within comfortable levels. Swap some running sessions for cycling or swimming. Avoid steep inclines in the short term, and be cautious with aggressive calf stretching if it causes your Achilles tendinitis to flare up.
Choose Achilles-friendly footwear
A stable shoe with appropriate heel support can reduce irritation at the back of the heel. Avoid sudden transitions to minimal-style shoes during a flare-up. In Singapore’s warm climate, avoid wearing loose sandals for long distances if your Achilles tendon is already sensitive. Symptoms of Achilles tendinitis can worsen with unsupportive footwear. An expert footwear assessment can help you with this.
Begin calf loading early, but correctly
Seated and standing raises are often a good start, progressing to heavier, slower resistance as tolerated. The calf muscles attach to your heel bone, so strengthening them reduces strain on the Achilles and is the foundation of Achilles tendinitis recovery.
Use short bouts of cold if it helps
Cold applied with ice packs or similar devices can alleviate post-exercise discomfort for some individuals. It is not a cure for Achilles tendinitis, but it can provide short-term comfort.
Consider basic first-aid principles for a flare-up
Brief rest from aggravating activity, along with compression and elevation, can be helpful if the swelling is noticeable, especially after a spike in loading.
Know when you may need more support
If pain and discomfort are significant, walking is difficult, or irritation is highly reactive, a clinician may advise a short period of immobilisation in a walking boot to calm things before rebuilding capacity. The goal is to stabilise the Achilles tendon, not to permanently eliminate loading.
These steps can help relieve early Achilles pain at the back of the heel and reduce the likelihood of a next-day flare-up.
How to Prevent Achilles Tendonitis from Coming Back
Preventing the recurrence of Achilles tendinopathy depends on gradually increasing your load, maintaining calf muscle strength, and avoiding sudden spikes that outpace the tendon adaptation. For runners, this usually means building volume and intensity stepwise, rotating in lower-impact sports sessions, warming up properly, and using footwear that suits your mechanics.
If you have identified biomechanical drivers, such as overpronation or ankle stiffness, custom orthoses or specific footwear changes can reduce repetitive strain on the Achilles tendon and support more consistent training. Sports such as cycling and swimming can be incorporated to reduce load on the Achilles tendon at the back of the heel while maintaining fitness.
How The Foot Practice Can Help
If the Achilles pain is limiting your running, training, or daily walking, you do not have to guess your way through it. The earlier you match the appropriate load to the correct diagnosis, the better your chances of resolving your Achilles tendon swelling and preventing recurrence of Achilles pain.
At The Foot Practice, we will identify the causes of your Achilles pain, guide a clear recovery plan, and help you return to activity, whether that is running at East Coast Park, playing sports, or simply moving comfortably through your day in the CBD. Book a sports podiatry assessment at The Foot Practice in Singapore today.
