Calf raises are widely accepted as an effective, non-surgical treatment for chronic Achilles tendon pain. When performed correctly, this simple exercise is a powerful tool in rehabilitation. The benefits come from a specific type of muscle action called eccentric loading, which directly encourages the tendon to heal. Understanding the precise execution of this intervention is the first step toward recovery.
Understanding Achilles Tendinopathy
The Achilles tendon is the largest tendon in the body, connecting the calf muscles—the gastrocnemius and soleus—to the heel bone. It handles immense force during walking, running, and jumping, making it susceptible to overload injuries. Historically, pain in this region was often labeled “tendonitis,” implying inflammation.
However, the more common and chronic condition is tendinopathy, which describes a non-inflammatory degeneration and disorganization of the tendon’s collagen fibers. This structural breakdown usually occurs not from a single traumatic event but from cumulative overload, such as a sudden increase in running mileage or improper footwear.
The Mechanism of Eccentric Loading
The benefit of calf raises lies in eccentric loading, which is the controlled lengthening of the muscle-tendon unit under tension. During a calf raise, the eccentric phase is the slow, deliberate lowering of the heel after pushing up. This action creates mechanical stress that stimulates the tendon’s cells to remodel its structure.
This mechanical tension forces the disorganized collagen fibers to realign and synthesize new, healthier collagen. The process switches the tendon from a degenerative state toward a more robust, healthy structure, increasing its tensile strength and stiffness. By progressively exposing the tendon to controlled, heavy loads, eccentric exercises prompt the tissue to adapt and become more resilient to the stresses of daily life and athletic activity.
Proper Protocol for Calf Raise Rehabilitation
Execution and Repetition
The success of calf raises depends on adhering to a specific and consistent protocol, often referred to as the Alfredson protocol. This regimen requires performing the exercise twice daily for 12 weeks to achieve structural changes. A standard protocol involves completing three sets of 15 repetitions for both straight-knee and bent-knee variations.
The exercise is best performed standing on a step, allowing the heel to drop below the forefoot for a full range of motion. The technique is to push up using both legs, then lift the unaffected leg, and slowly lower down on the affected leg only. The eccentric phase should take approximately three seconds per repetition to maximize the loading stimulus. The straight-knee variation targets the gastrocnemius muscle, while the bent-knee variation isolates the deeper soleus muscle.
Pain Management
A significant aspect of this rehabilitation is the need to work through some discomfort. The exercises are often performed with a tolerable amount of pain, up to about a three out of ten on a pain scale.
However, the pain should not be sharp or worsen significantly during the exercise or in the following hours. If the tendon is acutely sensitive, especially with insertional tendinopathy near the heel bone, the exercises should begin on flat ground to avoid excessive stretching.
Integrating Calf Raises into a Recovery Plan
Calf raises are a central component, but they must be integrated into a complete recovery strategy for long-term success. It is advised to begin the loading program after any initial acute pain and swelling have subsided. The goal is gradual, progressive overload, meaning the intensity of the exercises must slowly increase over time. Progression is achieved by adding weight, such as holding a dumbbell or using a weighted backpack. The weight should be increased systematically to match the ultimate load requirements of the individual’s activity level, ensuring the tendon adapts to future demands.
Complementary treatments include modifying activities to reduce initial strain, such as temporarily decreasing running distance. Gentle, static stretching can be integrated to maintain mobility, but aggressive stretching should be avoided, particularly in the early stages. A professional consultation is warranted if the pain intensifies, or if no noticeable improvement occurs after six to eight weeks of consistent effort. Consistent adherence and patience are necessary, as the biological process of tendon remodeling takes a minimum of three months to complete.