The effect of a 3-month exercise programme on the functional status of frail elderly patients. The aim of this study was to assess the effect of a 3-month exercise programme on the functional status of frail elderly patients. In a multicentre prospective randomized controlled trial, frail elderly patients aged >/= 70 years with a Mini-Mental State Examination (MMSE) score of >/= 20 were randomly allocated to two treatment groups: an exercise group and a control group. Frailty was defined according to the well-known criteria for the frailty phenotype. An exercise programme using the principles of functional-motor training for the upper and lower limbs was conducted over 12 weeks. Patients were evaluated at baseline, after 12 weeks and 3 months, using the Functional Independence Measure (FIM), an instrument measuring functional recovery in all the various activities of daily living, and the Frailty Index, which provided an estimation of the degree of frailty. The assessment consisted of three evaluations of the patient by a physician and three evaluations of the patient's caregiver. The final sample consisted of 50 subjects: 23 in the exercise group and 27 in the control group. After 12 weeks, the exercise group showed significant improvement in the mean total score of the FIM (36.6%), compared with the control group (14.8%). At the final assessment, the mean total score of the FIM had increased by 45.2% in the exercise group, compared with 15.4% in the control group. Both groups showed an improvement in their Frailty Index after 12 weeks, with no significant difference between the two groups at the end of the study. An appropriate exercise programme (combined with other physiotherapy interventions) can improve functional status in the frail elderly. In particular, the study demonstrated that this functional improvement is maintained for at least 3 months after the end of the exercise programme. This improvement is associated with a reduction in the level of frailty. The study suggests that functional-motor training programmes should be recommended for the frail elderly.