MUSCLE STRENGTH IN HEALTHY PEOPLE AND IN PATIENTS SUFFERING FROM RECENT-ONSET INFLAMMATORY ARTHRITIS

Neuromuscular function was compared among 20 patients with relatively recent onset (symptomatic period 17 +/- 24 months) rheumatoid arthriti s (RA) (experimental group; EG), and 20 age- and sex-matched healthy p eople (control group; CG). The comparison was repeated after a period of 6 months, when 16 patients had carried out progressive strength tra ining. At baseline maximal grip strength and maximal dynamic unilatera l strength of the knee extensors in the EG were significantly (P < 0.0 5) lower in comparison to the CG. The groups did not differ from each other in maximal isometric strength of the trunk flexors and extensors or the knee extensors. The 6-month dynamic strength training in the E G resulted in significant increases in maximal dynamic strength of the knee extensors (P < 0.001), in isometric grip strength (P < 0.001) an d in isometric strength of the trunk flexors (P < 0.05) and extensors (P < 0.05) to the level of the healthy controls. Only minor changes to ok place in explosive strength and maximal isometric strength of the k nee extensors. Erythrocyte sedimentation rate (P < 0.001), Ritchie's a rticular index (P < 0.01) and modified health assessment questionnaire (P < 0.01) improved significantly during the training period. The res ults suggest that inflammatory arthritis decreases dynamic and/or isom etric muscle strength in selected muscle groups of the body already in the early stages of disease. However, progressive dynamic strength tr aining rapidly increases the neuromuscular performance capacity of the patients even to the level of healthy people without detrimental effe cts on disease activity.