A study published in PLOS ONE shows that symptoms of chronic fatigue syndrome can be provoked by imposing a mild to moderate strain to the muscles and nerves.
The study included 80 individuals, 60 with CFS and 20 without CFS, who reported their levels of fatigue, body pain, lightheadedness, concentration difficulties, and headache every 5 minutes while undergoing 15 minutes of either a passive supine straight leg raise or a sham leg raise that did not cause strain. Participants were contacted 24 hours later and again reported their symptoms.
Compared with those with CFS who underwent the sham leg raise, individuals with CFS who underwent the passive leg raise that actually strained their muscles and nerves reported significantly increased body pain and concentration difficulties during the procedure. After 24 hours, these same individuals who underwent the true strain also reported greater symptom intensity for lightheadedness and the overall combined score for symptoms. The individuals with CFS who underwent the true strain also reported more symptoms during, and 24 hours after the true strain compared with individuals without CFS.
“These findings have practical implications for understanding why exercise and the activities of daily living might be capable of provoking CFS symptoms,” said Kevin Fontaine, PhD, University of Alabama at Birmingham, Birmingham, Alabama. “If simply holding up the leg of someone with CFS to a degree that produces a mild to moderate strain is capable of provoking their symptoms, prolonged or excessive muscle strain beyond the usual range of motion that occurs during daily activities might also produce symptom flares.”
“The lengthwise strain applied to the nerves and muscles of the lower limb is capable of increasing symptom intensity in individuals with CFS for up to 24 hours, indicating that increased mechanical sensitivity may be a contributor to the provocation of symptoms in this disorder,” added lead author Peter Rowe, MD, Johns Hopkins Children’s Center Chronic Fatigue Clinic, Baltimore, Maryland.
The researchers intend to extend this work to further understand the effects that strains to the muscles and nerves have on CFS, as well as whether specific physical therapy methods could be used to improve neuromuscular function to reduce symptoms.
SOURCE: University of Alabama at Birmingham