The effect of 30 min cycle ergometry on ankylosing spondylitis.

The effect of 30 min cycle ergometry at approximately 100 W (mean 98.8 W; range 34-151 W) in 11 male patients who had no hip involvement were studied. In most patients, exercise produced immediate increases in spinal flexibility and bilateral cervical tilt, and a reduction in pain. However, these improvements steadily waned and all had disappeared by 3-5 h. Exercise induced marked changes in the numbers of circulating leucocytes and platelets, and in the distribution of lymphocytes subsets, similar to those previously reported to occur in individuals without the disease. In a majority of patients there were positive associations (Kendall's tau test) between Schober's index and the platelet count, and negative associations between Schober's index and the percentage of CD4-positive cells over a 5 h period on the exercise day, whereas there were negative associations between the pain score and the leucocyte and neutrophil counts over a comparable period on a control day without exercise. We conclude that exercising those regions of the body unaffected by disease can elicit short-term beneficial effects by a systemically mediated mechanism(s).