NEW YORK (Reuters Health) – Postmenopausal women with fibromyalgia seem to have less physical strength and endurance than healthy women, so they might benefit from an appropriate training program, a new study by Finnish researchers suggests.

Fibromyalgia, which is characterized by pain, fatigue and difficulty sleeping, is most common in women after menopause, Heli Valkeinen of the University of Jyvaskyla and her colleagues note in a report in the International Journal of Sports Medicine, but most studies have focused on women 50 and younger.

Some research in premenopausal women has found lower-than-normal muscle strength and aerobic capacity, the researchers add, but fitness has not been investigated in postmenopausal women with fibromyalgia.

To determine whether women with fibromyalgia might experience a steeper decline in physical fitness after menopause than their healthy peers, the researchers looked at 23 women with the condition and a comparison group of 11 similar but fibromyalgia-free women. The average age for both groups was 58.

There was no difference between fibromyalgia patients and healthy women in upper body strength, but the women with fibromyalgia did have less muscle strength in their legs.

Upon exercise testing, the women in the fibromyalgia group reached exhaustion at a lower maximal heart rate, but oxygen uptake was the same in both groups. This suggests, Valkeinen and her team say, that the fibromyalgia patients were less able to “stand physical loading and resist overall fatigue.”

Quality of life was worse among the fibromyalgia patients. “Fatigue rather than pain appears to decrease the quality of life and limit the physical performance of the patients,” the researchers report.

They conclude, “The results suggest that more attention should be paid to train muscle performance, together with overall training of physical fitness, when developing rehabilitation programs for postmenopausal women with fibromyalgia.”

SOURCE: International Journal of Sports Medicine, May 2008.