SUZANNE BROADBENT, ROSANNE COUTTS

There is increasing evidence of immune system dysfunction in Chronic Fatigue Syndrome (CFS) but little is known of the regular exercise effects on immune cell parameters. This pilot study investigated the effects of graded and intermittent exercise on CD4 lymphocyte subset counts and activation compared to usual care. 24 CFS patients (50.2 ± 10 yr) were randomised to Graded exercise (GE), Intermittent exercise (IE) or usual care (UC) groups; 18 sedentary non-CFS participants (50.6 ± 10 yr) were controls (CTL) for blood and immunological comparisons. Outcome measures were pre- and post-intervention flow cytometric analyses of circulating lymphocyte subset cell counts, expression of CD3, CD4, CD25 and CD134, full blood counts and V[Combining Dot Above]O2peak RESULTS: Pre-intervention, CD3 cell counts and expression of CD4, CD25, CD134 and CD4CD25CD134 were significantly lower in GE, IE and UC compared to CTL (f < 0.05). Total lymphocyte concentration was significantly lower in GE and IE groups compared to CTL. There were significant post-intervention increases in (i) expression of CD4 and CD4CD25CD134 for GE and IE, but CD25 and CD134 for IE only; (ii) circulating counts of CD3 and CD4 for GE, and CD3, CD4, CD8, CD3CD4CD8, CD3CD16CD56, CD19 and CD45 for IE; (iii) neutrophil concentration for GE; (iv) V[Combining Dot Above]O2peak and elapsed test time for IE and GE, V[Combining Dot Above]Epeak for IE. Twelve weeks of GE and IE training significantly improved CD4 lymphocyte activation and aerobic capacity without exacerbating CFS symptoms. IE may be a more effective exercise modality with regard to enhanced CD4 activation in CFS patients.