Lumbar curvature in standing and sitting in two types of chairs: relationship of hamstring and hip flexor muscle length.

A purpose of this study was to determine the difference in the lumbar curves of subjects while they stood compared with while they sat in two chairs with different seat angles--the Balans Multi-Chair (BMC) and a standard conventional chair (SCC). An additional purpose was to determine the relationship between lumbar curvature and 1) anthropometric factors and hamstring and hip flexor muscle length during standing and during sitting in the two chairs and 2) amount of time spent sitting. Sixty-one men between 20 and 30 years of age served as subjects. Lumbar curve measurements were taken with a flexible ruler with the subjects first standing and then sitting in the two chairs. Hamstring and hip flexor muscle lengths were indicated by range-of-motion measurements taken with a gravity goniometer. Age, number of hours spent sitting per day, upper body length, and right leg length also were recorded. Subjects had significantly more lumbar extension when they sat in the BMC than when they sat in the SCC. Hip flexor length was the only factor that appeared to relate significantly to the difference between the standing lumbar curve and the lumbar curves in the BMC and the SCC.

Balance performance, force production, and activity levels in noninstitutionalized men 60 to 90 years of age.

The purpose of this study was to collect and analyze balance and muscle performance data obtained from 54 men aged 60 to 90 years. Balance was tested using the sharpened Romberg test (SR) and the one-legged stance test (OLST) on each foot with eyes open and eyes closed. A strain-gauge-based quantitative muscle tester (QMT) was used to measure force production. All torque values were normalized as a percentage of body weight. A self-report of activity level also was recorded. The results indicated that OLST scores and normalized torques of the hip flexors, extensors, and abductors had a positive correlation and that SR scores and normalized torques of the hip extensors and right hip abductors had a positive correlation. Subjects who considered themselves to be very active had a significantly higher SR eyes-closed balance time as compared with those who rated themselves as less active. Subjects who considered themselves to be very active also had significantly higher normalized torque values for most muscle groups tested. Negative relationships were shown between age and balance time and between age and force production.

Balance performance and step width in noninstitutionalized, elderly, female fallers and nonfallers.

The purposes of this study were to compare age, static balance performance, and step-width variables between elderly noninstitutionalized women with and without a history of falls and to determine the relationship between balance performance and step width. Each subject performed a maximum of three timed trials on the sharpened Romberg and one-legged stance tests with eyes open and with eyes closed. The first and best trial measurements were used for analysis. Each subject walked on paper walkways making ink prints for step-width measurements. The mean and the variability of each subject's step-width measurements were used for analysis. Data from 110 women, aged 60 to 89 years, were analyzed. The fallers (n = 26) had significantly lower values than the nonfallers (n = 84) on the best trial of the sharpened Romberg test in the eyes-open condition (t = 1.98, df = 108, p less than .05). No significant differences between fallers and nonfallers were revealed in age, the mean and variability of step width, the first trials of the balance tests, and the best trials on the other balance tests. For the total group, the mean measurements on the first trials were significantly lower than those on the best trials for each balance test. Small, but statistically significant (p less than .05), negative relationships existed between balance performance and the mean and variability of step width. The results of this study indicate that the methods of measuring balance and step width are clinically applicable, and the data of patients from a similar population sample may be compared with the data established in this study.

Balance performance among noninstitutionalized elderly women.

Descriptive data were collected regarding static standing balance of 71 noninstitutionalized elderly women as they performed two timed balance tests. All subjects performed the sharpened Romberg test and the one-legged stance test on each foot in four test conditions: 1) eyes open, 2) eyes closed, 3) shoes on, and 4) shoes off. Subjects were grouped and analyzed according to the following age ranges: 1) 60 to 64 years, 2) 65 to 69 years, 3) 70 to 74 years, 4) 75 to 79 years, and 5) 80 to 86 years. The best time of three trials was used for data analysis. The maximum balance time for the sharpened Romberg test was 60 seconds. For the one-legged stance test, a maximum balance time was 30 seconds. No significant difference was found between right and left or dominant and nondominant limbs while performing the one-legged stance test. No significant difference was found in mean balance time between subjects who had fallen versus those who had not fallen, nor between shoes-on and shoes-off test performance. Subjects' performance on the eyes-open test was consistently superior to their eyes-closed test performance (p less than .0001). The one-legged stance test mean balance time decreased significantly as age increased. More subjects reached the maximum balance time on the sharpened Romberg test than on the one-legged stance test. The results of this study indicate that additional research is needed in the area of balance maintenance among the elderly population.