WEDNESDAY, June 6, 2012 (HealthDay News) -- Exercise helps reduce pain from nerve damage caused by injury, diabetes and other conditions, according to a study involving rats.
Researchers found that exercise appears to ease this type of pain -- called neuropathic pain -- by reducing levels of inflammation-causing substances called cytokines.
Neuropathic pain is common but hard to treat. These findings suggest that exercise could provide an effective non-drug treatment for neuropathic pain, according to lead author Yu-Wen Chen, of China Medical University in Taiwan, and colleagues.
The study was published in the June issue of the journal Anesthesia & Analgesia.
For the study, researchers injured the sciatic nerve in rats and had them do exercise -- either swimming or treadmill running -- over a few weeks. These rats showed a 30 percent to 50 percent reduction in neuropathic pain, as assessed by their responses to temperature and pressure, according to a journal news release.
The researchers also found that exercise reduced levels of cytokines in the rats' sciatic nerve tissue and boosted levels of a protein called heat shock protein-27, which may have helped reduce cytokine levels.
Scientists note, however, that research with animals often fails to provide similar results in humans.
Conventional pain medications cannot control neuropathic pain. While antidepressants and antiepileptic drugs may help, they have significant side effects. Exercise is commonly recommended for patients with different types of chronic pain, but there are conflicting findings about whether it can help patients with neuropathic pain, the news release notes.
The American Chronic Pain Association has more about neuropathic pain.