Achilles tendon surgery, usually performed to repair a complete rupture, requires a prolonged and structured recovery before high-impact activities like running can safely resume. Healing takes many months due to the tendon’s limited blood supply, and the initial goal is preventing the tendon from being overstressed. Recovery is criterion-based, meaning time alone is not the deciding factor. The timeline for running typically ranges from six to twelve months, requiring consistent adherence to physical therapy and medical guidance.
Early Recovery Milestones
The first phase focuses on protecting the surgical repair and managing inflammation. The ankle is immobilized in a cast or splint with the foot pointed downward (plantarflexed) to keep tension off the repaired tendon. This position is maintained for weeks, during which no weight is placed on the surgical leg to prevent lengthening or tearing.
After the initial protective phase (usually two to six weeks), the patient transitions to a specialized walking boot, often with heel wedges to maintain slight plantarflexion. A gradual progression to full weight-bearing (FWB) typically occurs by four to six weeks post-surgery. This transition is controlled to apply increasing strain to the healing tendon while avoiding excessive ankle dorsiflexion, which can stretch the repair.
Early physical therapy, starting around six to twelve weeks, centers on restoring the ankle’s range of motion and normalizing the walking pattern. Initial strength work involves gentle calf exercises, focusing on muscle activation and endurance without high load. The goal is to achieve a stable, pain-free walking gait before considering advanced strengthening or impact activities.
Establishing Running Readiness
The transition from walking to running depends on meeting specific, measurable functional benchmarks, not just reaching a certain number of weeks post-operation. Clearance is typically considered no sooner than 12 to 16 weeks, though most protocols delay this until closer to six months. The primary physical measure is the Limb Symmetry Index (LSI), which compares strength between the injured and uninjured legs.
Calf muscle strength in the surgical leg must be at least 70 to 80% of the non-injured leg before a running program begins. Calf endurance is quantified through single-leg heel raise testing. Many protocols require the ability to perform 20 to 25 controlled single-leg heel raises, or to achieve a specified LSI percentage for heel rise height and repetitions.
Dynamic stability and power are also assessed through functional tests that mimic running demands. These include controlled single-leg squats and low-level plyometric exercises, such as double-leg hopping. Some advanced criteria require an LSI of 85% or greater on hop tests before progression to the running phase is approved.
The Phased Return to Running Protocol
Once readiness criteria are met, the return to running begins with a structured, gradual progression to safely reintroduce impact forces. The program is interval-based, alternating between short periods of running and longer periods of walking to manage the load on the Achilles. A common starting point is a conservative one-minute jog followed by three minutes of walking, repeated for a total session time of approximately 20 minutes.
This initial interval program is usually performed three to four times per week, with careful monitoring for any increase in pain or swelling. If the tendon tolerates the initial week without symptoms, the ratio is gradually shifted by increasing the running interval and decreasing the walk break. For example, the patient may progress to a two-minute run and two-minute walk interval in the following weeks.
Total running time and distance are increased, ensuring that a patient does not simultaneously increase both speed and duration. Running is kept at a low, sub-maximal intensity on flat, predictable surfaces, such as a treadmill or track. Only after the patient can run continuously for 20 to 30 minutes without pain is the program advanced to include changes in speed, incline, or more aggressive plyometric drills.
Individual Factors That Influence Recovery Timing
While the milestones provide a clear path, the speed of progression is influenced by several factors. The specific surgical technique used, whether a simple repair or a complex reconstruction, influences the initial protective period. The patient’s age and overall health status, particularly factors like diabetes or smoking, impact the body’s ability to heal tendon tissue effectively.
Fitness and Goals
Pre-injury fitness level and the patient’s ultimate goals also play a role. A recreational jogger may meet running criteria sooner than a competitive athlete aiming for maximal power.
Adherence and Complications
Strict adherence to the physical therapy program, including consistency with strengthening and mobility exercises, directly correlates with the rate of functional improvement. Patients who experience persistent pain or swelling three months after surgery may face a delayed recovery timeline for regaining calf endurance.