Relationship between handgrip strength, peripheral muscle strength, and respiratory muscle endurance in women with fibromyalgia: a cross-sectional study

Fibromyalgia (FM) is a disease characterized by generalized and chronic musculoskeletal pain. It is common, the presence of other symptoms such as fatigue, depression, sleep disorders, leading patients to adopt a sedentary lifestyle. Objective: Verify the muscular and respiratory strength of women with FM. Method: Is a cross-sectional study that evaluated 41 women with clinical diagnosis of FM. We analyzed handgrip strength (HS), the strength of the lower limbs, and respiratory muscle endurance using the spirometric maneuver. Results: Patients with FM had a significant reduction in HS, both in the dominant and non-dominant upper limb. Furthermore, peripheral muscle strength in the lower limbs was reduced because on average, participants exceeded the normative five-repetition sit-to-stand test times stipulated for the age groups. Approximately two-thirds of the sample had maximal voluntary ventilation values below the lower limit of normality. We detected inverse and moderate correlation between peripheral muscle strength and HS of non-dominant upper limb (r= −0.472; p= 0.002) and inverse and weak correlation with the HS of dominant upper limb (r= −0.374; p= 0.016); weak correlations between respiratory muscle endurance and HS of dominant upper limb (r= 0.299; p= 0.058), HS of non-dominant upper limb (r= −0.317; p= 0.043), and peripheral muscle strength (r= −0.372, p= 0.017); and strong correlation between HS of dominant upper limb and non-dominant upper limb (r= 0.899; p