Sixty-six elderly women aged over 65 years old were consecutively selected from patients of the Osteometabolic Disease Outpatient Clinic of the Rheumatology Division, University of São Paulo. Only patients with osteoporosis, classified according to the World Health Organization  were included; with a bone mineral density (BMD) T-score lower than −2.5 standard deviation (SD), in the lumbar spine, femoral neck or total femur region.
The following women were excluded: those with secondary osteoporosis, visual deficiency, severe auditive deficiency, or vestibular alteration of important clinical status, such as women who used assisted walking devices or who were unable to walk independently more than 10 meters ; those who planned to be out of town for more than 4 weeks during the 12-month study; and women who presented absolute or relative contraindications for exercise training according to the American College of Sports Medicine .
The patients were randomized consecutively into two groups: the group submitted for the Balance Training Program (Intervention Group), consisting of 34 patients; and the Control group, consisting of 32 patients without intervention. The Control group only received treatment for osteoporosis and orientation to prevent falls and return regularly (3-monthly follow-ups) to the Osteometabolic Disease Outpatient Clinic. All patients read and signed a term of free informed consent that described the procedures which would be realized during the research.
Measured variables: interview and medical chart records
Personal, family and clinical data were evaluated through an interview and medical chart records, with emphasis on the history of fractures, number of falls in the preceding year, use of medication for osteoporosis, and use of medication that favored the risk of falling, such as hypnotics, hypotensors and antidepressants.
Functional state evaluation
Static and dynamic balance and mobility were evaluated in all patients, before and at the end of the trial, by a physiotherapist who was blinded to the distinct group (Intervention, Control).
The Berg Balance Scale (BBS) is based on 14 items common to daily life activities used to evaluate functional balance . The maximum score that can be achieved is 56, and each item possesses an ordinal scale of five alternatives which varies from 0 to 4 points.
The test is simple, easy to administer and accompanies the evolution of elderly patients. It only requires a ruler and a watch and takes approximately 15 minutes to execute . A score lower than or equal to 45 is considered evidence of altered balance .
Static balance was evaluated by the Clinical Test of Sensory Interaction for Balance (CTSIB), which consists of six sensory conditions (1: eyes open and firm surface, 2: eyes closed and firm surface, 3: eyes open, visual conflict and firm surface, 4: eyes open and unstable surface, 5: eyes closed and unstable surface, and 6: eyes open, visual conflict and unstable surface).
Static balance is considered to be altered when an individual cannot remain at least 30 seconds in each of the six conditions .
Improvement in the test was defined as the capacity to complete the test during the final evaluation when unable to complete the same in the initial evaluation.
Functional mobility was evaluated by the Timed “Up & Go” Test (TUGT) , which registers the time an individual takes to get up out of a chair, walk 3 meters, turn around, walk back and sit down again.
Elderly individuals without balance deficit are capable of completing the test in less than 10 seconds.
The number of falls in the year prior to the study  was solicited and noted in the initial evaluation and at the end of the trial (final evaluation). During the year of the study, patients in both groups received a diary and were orientated to write down the days that they fell.
At the end of the study, the difference in the number of falls/patient (final evaluation - initial evaluation) was compared between the Intervention Group and Control.
The Balance Training Program consisted of 1 hour of exercises realized once a week, with a total of 40 classes, supervised by an experienced physiotherapist. This program was realized in a club (Associação Atlética Acadêmica Oswaldo Cruz - AAAOC) belonging to the Clinics Hospital, School of Medicine, University of São Paulo, located near to the Hospital. The balance exercises described by Tinetti and Suzuki [3, 11] were used. The type and mild to moderate intensity of the exercises used in the present study were chosen so that they could also be performed by elderly patients at home . A list of weekly attendance controlled the absences of each patient.
Basic warm-up and stretching exercises
Prior to training, the patients participated in 15 min of warm-up and stretching exercises, consisting of head rotation, shoulder rotation and stretching of the upper and lower limbs. Walking was performed for 15 min with the supervision of a physiotherapist, who associated exercises for the upper limbs throughout the walk.
Balance was realized in dynamic and static positions for a period of 30 min. This consisted of walking in the tandem position (one foot in front of the other), walking on the tips of the toes and on the heel, walking sideways, walking while raising the leg and the contra-lateral arm, standing on one leg, and standing in the tandem position, while gradually increasing the period of permanence in these last two static positions [3, 31].
The patients were instructed and encouraged to continue the same exercises at home at least three times a week for 30 min. A manual with instructions and illustrations for each exercise was distributed. The frequency of participation in the home-based exercises was noted each week by the physiotherapist.