Tendonitis is the painful irritation of a tendon often caused by overuse. Tendons are tough, fibrous cords connecting muscle to bone. When they become painful, the surrounding muscles often feel tight, leading people to believe stretching will provide relief and accelerate healing. However, the initial reflex to stretch a painful tendon is often counterproductive. Current medical understanding suggests stretching may hinder the body’s repair process.
Understanding Tendonitis and the Risk of Stretching
The term “tendonitis” technically refers to acute inflammation, but most chronic tendon pain is actually tendinopathy or tendinosis. Tendinopathy involves the degeneration and disorganization of the tendon’s collagen fibers. This structural change means the tendon has lost its normal, organized capacity to handle load.
Stretching the affected area can worsen this degeneration by subjecting damaged fibers to excessive tension and compression. When a tendon is stretched, especially if it wraps around a bony prominence like the heel or hip, it is compressed against the bone. This compressive load further disrupts the delicate collagen structure. For example, stretching the calf muscle to relieve Achilles pain compresses the Achilles tendon against the heel bone.
Aggressive stretching causes disorganized proteins to swell with water, impairing the tendon’s function and increasing pain. The goal of treatment is to protect the tendon structure and rebuild its strength, not to elongate the tendon or surrounding muscle. Stretching may feel temporarily relieving because it affects the muscle, but it often aggravates the underlying tendon pathology.
Immediate Steps: Actions That Irritate Tendons
When tendon pain first appears, the priority is to reduce irritation and protect the tendon from further mechanical stress. The initial activity that caused the pain must be stopped or significantly modified. Continuing the same movement patterns that caused the overuse injury perpetuates the degenerative cycle.
Individuals should actively avoid ballistic movements, which are quick, bouncing motions that impose sudden tension on the tendon. Deep or aggressive massage directly on the painful area should also be avoided in the acute phase, as this adds to compressive and shear forces. The focus should be on relative rest—ceasing the aggravating activity while maintaining general movement—rather than complete immobilization, which can weaken the tissue. The goal is to calm the tendon down before introducing therapeutic loads.
Safe Rehabilitation: The Power of Controlled Loading
Once the initial pain subsides, the most effective long-term treatment for tendinopathy is a carefully controlled, progressive loading program, not stretching. This approach strengthens the tendon and increases its capacity to tolerate the demands of daily life and physical activity. The program progresses through specific types of muscle contractions designed to stimulate repair and realignment of the collagen fibers.
The first phase often involves isometric loading, which means contracting the muscle without changing its length or the angle of the joint. This static hold has been shown to offer a temporary analgesic effect, helping to reduce pain almost immediately for some tendons. Isometric contractions are usually performed at a heavy intensity, around 40 to 70 percent of a person’s maximum effort, held for 45 to 60 seconds, and repeated several times a day.
The rehabilitation then progresses to isotonic exercises, which include both concentric and eccentric phases. Eccentric loading, where the muscle lengthens under tension, is particularly effective for tendons. This slow, controlled lengthening helps to rebuild the tendon’s structure and improve its ability to absorb and release energy, which is essential for activities like running or jumping.
Modern protocols often favor heavy-slow resistance (HSR) training. This training includes both the lifting (concentric) and lowering (eccentric) phases, performed slowly and with a heavy weight to promote collagen turnover and strength. Exercises must begin lightly and gradually increase in weight or duration, a process called progressive overload. This structured strength training is fundamentally different from stretching; it is a biomechanical stimulus designed to increase the tendon’s strength and resilience.
Recognizing When Professional Help is Necessary
While initial self-management with rest and modification of activity is appropriate, certain signs indicate the need for professional medical evaluation. If the tendon pain persists beyond one to two weeks despite reducing the aggravating activity, a physician or physical therapist should be consulted. A professional can provide an accurate diagnosis, distinguishing between various tendon conditions and ruling out other sources of pain.
Clear indicators for seeking help include:
- Pain that interferes with sleep or basic daily tasks.
- Worsening swelling or noticeable weakness in the affected limb.
- A sudden, sharp pain accompanied by a popping or snapping sound, which signals a potential tendon rupture.
A physical therapist is particularly well-suited to design a precise, progressive loading program tailored to the specific needs of the injured tendon.