Background Ankylosing spondylitis (AS) is a systemic inflammatory disease that affects the physical capacity of patients globally. Exercises are recommended to the management of patients with AS, although the benefits of specific exercise programs are not yet well defined.
Objectives To evaluate the effectiveness of a progressive muscle strengthening program using a Swiss ball in improving functional capacity, muscle strength, disease activity, mobility and quality of life of patients with AS.
Methods Sixty patients were randomized to intervention group (IG) or to control group (CG), with 30 patients in each group. Eight exercises were done by GI with free weights on a Swiss ball, 2 times per week for 16 weeks. Loads were reassessed and increased every 4 weeks. The GC continued drug therapy without any exercise, on a waiting list. The evaluations were performed by a blinded evaluator immediately before randomization and at 4, 8, 12 and 16 weeks after initiation of the study. Functional capacity were evaluated using the BASFI (Bath Ankylosing Spondylitis Functional The Index), HAQ-S (Health Assessment Questionnaire for Spondyloarthropathies), the 6-minute walk test and the Time Up and Go test. Muscle strength was assessed by the 1-repetition maximum (1 RM) test. Disease activity was measured by BASDAI (The Bath Ankylosing Spondylitis Disease Activity Index) and by dosage of ESR and C-reactive protein. The BASMI (The Bath Ankylosing Spondylitis Metrologyl Index) was used to assess spinal mobility and the SF-36 questionnaire to assess quality of life. Patients were also evaluated by Likert scale for satisfaction. In addition, the amount of analgesic and non-steroidal anti-inflammatory used was controlled.
Results The groups were homogeneous at baseline for clinical and demographic characteristics. There was a statistically significant difference between the two groups in the improvement of strength in IG compared to the CG for the muscles used in the exercises: abdominal (p = 0.003), rowing exercises (p = 0.02), squat (p = 0.01), triceps (p = 0.021) and reverse fly (p = 0.02). The IG also improved the 6-minute walk test (p = 0.005) at week 16 compared with the CG. We also found a statistically significant difference between groups in the Likert scale at all times (p <0.001) with IG showing greater treatment satisfaction. We found no differences between groups in other variables and there was no worsening of disease activity in IG.
Conclusions The progressive muscle strengthening using a Swiss ball is effective in improving muscle strength and walking performance in patients with AS. The exercise program has shown good tolerance assessed by patient satisfaction without deleterious effects on disease activity.
American College of Sports Medicine. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med Sci Sports Exerc. 2009 Mar;41(3):687-708. Review.
Dagfinrud, H.;Kvien, T. K.; Hagen, K. B. Physiotherapy interventions for ankylosing spondylitis. Cochrane Database Syst Rev, p.CD002822, 2008.
Disclosure of Interest None Declared