John A. Ward

Physiological factors associated with falls in older community-dwelling women

OBJECTIVE: To determine the prevalence of impaired vision, peripheral sensation, lower limb muscle strength, reaction time, and balance in a large community‐dwelling population of women aged 65 years and over, and to determine whether impaired performances in these tests are associated with falls.

The Effect of a 12‐Month Exercise Trial on Balance, Strength, and Falls in Older Women: A Randomized Controlled Trial

OBJECTIVE: To determine whether a 12‐month program of regular exercise can improve balance, reaction time, neuromuscular control, and muscle strength and reduce the rate of falling in older women.

Balance, reaction time, and muscle strength in exercising and nonexercising older women : a pilot study

Twenty-one women, aged 57 to 75 years, who had been taking part in exercise programs for periods of 12 months or more underwent tests of muscle strength, reaction time, proprioception, and body sway. The performance of these women in the tests was compared with 21 women of the same age who were not taking part in any organized physical activity and were not exercising more than 30 minutes a day. The women who had been taking part in the exercise program performed significantly better in the tests of quadriceps strength, reaction time, and sway on a compliant surface than the nonexercising women. The exercisers also had lower body mass index scores. These pilot results suggest that exercise may play a role in improving a number of sensori-motor systems that contribute to stability, and that exercise of this nature may help prevent falls in older women.

The effects of a community exercise program on fracture risk factors in older women.

One hundred and seventy-nine women aged 60–85 years (mean age 71.6 years, SD 5.3 years) were randomly recruited from the community to participate in a 12-month randomized controlled trial to determine whether a program of twice-weekly structured exercise has beneficial effects on three factors associated with osteoporotic fractures: quadriceps strength, postural sway and bone density. At initial testing, there were no significant differences in the strength, sway and bone density measures (assessed at the hip and lumbar spine) between the exerciser and control groups. The exercise classes included strengthening, coordination and balance exercises, and approximately 35 min of each class comprised weight-bearing exercise. The mean number of classes attended for the 68 exercisers who completed the program was 59.8 of the 82 classes (72.9%). At the completion of the trial, the intervention group showed significant improvements in quadriceps strength and sway but not bone mineral density when compared with the control group. Indices of fracture risk, indicated by (i) the sum of standard score results and (ii) the sum of quartile grades of the femoral neck bone density, sway and strength measures, decreased significantly in the exercisers at the end of the trial compared with the controls. In conclusion, the program of general aerobic exercise may have reduced overall fracture risk, even though it did not significantly increase bone density. Further long-term studies are required that include acceptable weight-loaded exercises to determine optimal programs for reducing fracture risk factors by improving bone density as well as strength and balance.

Sensori-motor Function in Older Persons with Diabetes

Twenty‐five persons with diabetes (aged 55–83 years) who were living independently in the community, and 40 age‐ and sex‐matched non‐diabetic controls were assessed for tactile sensitivity, vibration sense, proprioception, quadriceps strength and body sway. In both men and women, those with diabetes performed significantly worse in tests of body sway on firm and compliant surfaces compared with the control subjects after controlling for weight and body mass index. The female diabetic subjects also performed significantly worse in tests of peripheral sensation and strength compared with controls. Age‐related declines in sensori‐motor function were greater in the diabetic group (r = 0.55–0.75) than in the controls (r < 0.44), while within the diabetic group, duration of diabetes and vibration sense were significantly correlated with sway on a compliant (foam rubber) surface with the eyes open (partial r = 0.52, p < 0.01 and r = 0.55, p < 0.01, respectively). The study findings provide evidence that older people with diabetes have problems with stability and related sensori‐motor factors which may place them at increased risk of falls.

Physiologic, health and lifestyle factors associated with femoral neck bone density in older women

Three hundred eleven women aged between 60 and 91 years (mean age 72.2) who were randomly recruited from the community underwent bone density assessments of the femoral neck. Two complementary multivariate techniques were used to assess the relationships between femoral neck bone density and a range of anthropometric, health, and lifestyle measures. Stepwise multiple linear regression analysis revealed age, weight, height, quadriceps strength, and lifelong smoking to be variables that independently and significantly explained part of the variance in femoral neck bone density within the group. Multiple logistic regression revealed that after adjusting for established predictors of bone mineral density, age, height, and weight, reduced quadriceps strength, lifelong smoking, and little childhood activity were significantly associated with low bone density (< 0.70 g/cm2), whereas superior quadriceps strength, nonsmoking, and high levels of current physical activity were significantly associated with high bone density (> 0.84 g/cm2). In contrast, current calcium intake was not significantly associated with bone density. The study findings highlight possible public health initiatives for minimizing age-related femoral neck bone loss in older women.