The Achilles tendon connects your calf muscles to your heel bone and powers every step you take — walking, running, and jumping all depend on it. Because it takes on so much force, it's one of the more common sources of heel and lower leg pain. Knowing what it does and what can go wrong is the first step toward feeling better.
Where your Achilles tendon is and what it does for you
The Achilles tendon runs down the back of your lower leg, from the base of your calf to the bump at the back of your heel. It's the longest and strongest tendon in your body, and it carries an enormous load — absorbing forces several times your body weight with every stride. When it's working well, you don't notice it. When it's not, you feel it with nearly every move you make. Tightness, tenderness along the back of your heel, or a sharp ache after activity are all common signs that this tendon is under more stress than it can handle.
What causes Achilles tendon pain
Achilles tendon pain most often develops gradually rather than from a single injury. Overuse is the most common culprit — too much activity added too quickly, especially running or high-impact exercise. Tight calf muscles put extra strain on the tendon, and changes in footwear, running surface, or training load can all tip the balance from manageable to painful. In some cases, a partial or complete tear can occur, which causes sudden, sharp pain and makes it difficult or impossible to bear weight.
Why Achilles tendon problems are easy to push through — until they're not
Many people assume heel or calf pain will resolve on its own with a few days of rest, and it sometimes does — temporarily. But underlying tightness or overload tends to return with activity if nothing changes. Addressing the mechanics behind the pain, rather than just waiting it out, is what actually helps it stay better.
How Sword Health can help
A physical therapist can pinpoint exactly what's driving your Achilles tendon pain and build a plan to address it — whether that's strengthening your calf, adjusting how you move, or guiding you through a gradual return to activity. Sword makes that care available from home, on a schedule that works for you.
About the author
Carolina Moreira
Medical Director of Clinical Development at Sword Health
