Although treadmills provide a more cushiony surface than paved roads do, your calves are still susceptible to injury, especially if you set the treadmill at a steep incline. Improper form while running on the treadmill and overworked muscles can increase your risk of damaging your calves. Calf pain is typically caused by a tear in the muscle fibers. You can also bring on more serious damage, such as compartment syndrome and Achilles tendinitis, while running on the treadmill.
In many ways treadmills are a safer alternative to running on concrete streets or paved paths; they offer a controlled environment and softer surface. But the more you shift your weight and alter your stride, the more stress you put on your calves. To help prevent damage to the calves, set the grade at a low to moderate incline and increase and decrease speed gradually and sparingly.
Your calf is made up of two muscles: the soleus, which controls the point and flex of your foot, and the gastrocnemius, which controls your knee muscles. Pain in the lower calf usually signifies a strain in the soleus muscle, whereas pain throughout the entire calf indicates a strain in the gastrocnemius. Calf pain can manifest as a dull ache or as a stabbing pain. Whether it's cramps or more severe pain, calf strain is typically caused by dehydration, muscle fatigue or low levels of sodium, calcium or potassium.
Compartment syndrome occurs when there is increased pressure within the calf muscle. It causes muscle and nerve damage due to decreased blood supply. Symptoms include severe pain, numbness and lack of mobility. The only treatment for acute compartment syndrome is surgery in which the muscle compartment is cut open to decrease pressure and revitalize blood flow.
A common injury among runners, particularly sprinters, Achilles tendinitis reveals itself as heel pain and is often a precursor to a ruptured tendon. A ruptured tendon or muscle can take anywhere from four to eight weeks to heal. Running too many miles at too steep an incline makes you more vulnerable to developing tendinitis. According to MayoClinic.com, not stretching your calves and wearing worn out shoes can also increase your risk of developing Achilles tendinitis.
To prevent these and other conditions, be sure to stretch and warm up before running on the treadmill. Wear running shoes that provide enough support and cushion for your muscles, joints and tendons. Stay hydrated before, during and after your run and fuel your body with electrolytes.
Amy Lucas is a writer for the Underground Health Reporter and Gaiam websites, and for Bestcovery.com. She has written for business and personal websites and been published in educational publications, including Random House's "1,296 ACT Practice Questions" and in her own series of SAT books and DVDs, "Private Tutor SAT, Your Compete SAT Test Prep Course."