Details of randomised patients Relaxation (n=67) Exercise (n=69) Median (interquartile range) age (years) 45 (38-52) 48 (38-56) Median (interquartile range) duration (years) 4 (3-9) 6.5 (3-10) Median (interquartile range) education (years) 11 (10-14) 12 (10-14) Single 33 35 Women 64 62 Currently employed 14 23 Receiving social security benefits 49 40 Taking analgesics 27 27 Taking antidepressants 20 16 Fulfil criteria for chronic fatigue syndrome 48 47 Mean (SD) SF-36 summary z scores*: Mental component 3.9 (1.6) 3.6 (1.3) Physical component 3.9 (1.1) 3.7 (0.9) * Compared with means of UK populations.