Strength training induced adaptations in neuromuscular function of premenopausal women with fibromyalgia: comparison with healthy women

Abstract

Objective: To investigate the effects of 21 weeks' progressive strength training on neuromuscular function and subjectively perceived symptoms in premenopausal women with fibromyalgia (FM).

Methods: Twenty one women with FM were randomly assigned to experimental (FM(T)) or control (FM(C)) groups. Twelve healthy women served as training controls (H(T)). The FM(T) and H(T) groups carried out progressive strength training twice a week for 21 weeks. The major outcome measures were muscle strength and electromyographic (EMG) recordings. Secondary outcome measures were pain, sleep, fatigue, physical function capacity (Stanford Health Assessment Questionnaire), and mood (short version of Beck's depression index).

Results: Female FM(T) subjects increased their maximal and explosive strength and EMG activity to the same extent as the H(T) group. Moreover, the progressive strength training showed immediate benefits on subjectively perceived fatigue, depression, and neck pain of training patients with FM.

Conclusions: The strength training data indicate comparable trainability of the neuromuscular system of women with FM and healthy women. Progressive strength training can safely be used in the treatment of FM to decrease the impact of the syndrome on the neuromuscular system, perceived symptoms, and functional capacity. These results confirm the opinion that FM syndrome has a central rather than a peripheral or muscular basis.

Figure 1

Mean (SD) bilateral leg extension (1 RM) in fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods.

Figure 2

Mean (SD) bilateral isometric leg extension forces in fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods.

Figure 3

Mean (SD) maximal integrated electromyographic (iEMG) activity of the vastus medialis and vastus lateralis muscles in maximal isometric leg extension in fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods. (A) left leg; (B) right leg.

Figure 4

Coactivation percentage of the biceps femoris muscle during maximal isometric leg extension in fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods.

Figure 5

Mean (SD) maximal rate of force development in bilateral isometric leg extension in fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods.

Figure 6

Mean heights (SD) in maximal vertical squat jump among fibromyalgia (FM_T) and healthy (H_T) trainers and fibromyalgia controls (FM_C) during the four week control and 21 week strength training periods.