Tolerance to submaximal eccentric exercise in women with and without fibromyalgia, moving away from anecdotal beliefs

Abstract

We have shown people with fibromyalgia experience exacerbated pain in the exercising limb up to three days following submaximal isometric and concentric exercise however, the pain response following eccentric exercise has not been investigated. This study investigated the change in experimental pain up to two days following submaximal eccentric exercise while clinical pain was assessed through the 7-day recovery period in women with and without FM. Eighteen women with fibromyalgia (49.1±11.8yr, BMI: 31.4±7.6) and 18 controls (49.5±10.1yr, BMI: 27.1±4.8) completed session 1 (exercise) and session 2 (recovery assessment) separated by 2 days; session 1 included a 10-minute bout of submaximal (20% of maximal voluntary contraction) eccentric exercise with the right elbow flexors. Pressure pain thresholds (PPTs), mechanical pain summation, and punctate pain summation were assessed before, immediately after exercise, and in session 2. Clinical pain (0-10 NRS) in the exercising arm and whole-body was assessed before, during, immediately after, and up to seven days following the exercise bout. PPTs and mechanical pain summation did not change immediately following exercise or session 2 (Time, p>0.05). Punctate pain summation changed following exercise (Time x Summation, p=0.003) however, post hoc analysis did not reveal a significant difference immediately after exercise (p=0.296) or at session two (p=0.03). The fibromyalgia group reported greater increases in exercising arm pain during (Time x Group, p