Pedometer-Determined Physical Activity and Health Variables in African-American Women (40-62 years of age)

The purpose of this study was to evaluate the relationship between pedometer-determined physical activity, measured in steps per day, and several health variables in middle-aged, African-American women. Height, weight, waist circumference, hip circumference, and % body fat were measured in 69 African-American females (mean age 51.4 ± 5.4 years). Subjects wore a pedometer for 7 consecutive days after their laboratory visit and average steps/day were compared to each health variable. For statistical analyses, subjects were categorized into 3 different groups based on their physical activity level. The categories were < 5,000 steps/day, 5,000-7,499 steps/day, and > 7,500 steps/day. A one-way analysis of variance (ANOVA) was performed to examine the health variables among the three groups. Partial correlation coefficients controlling for age were calculated for steps/day and BMI, body fat, waist and hip circumference, and WHR. Significance was set at P< 0.05 for all tests.

This is the first study to investigate the relationships between steps/day and % body fat in middle-aged, African-American females. Significant differences were found among the least active and most active groups for age (P=0.013), average steps/day (P<0.001), body weight (P=0.003), BMI (P=0.005), % body fat (P<0.001), waist circumference (P=0.004), and hip circumference (P=0.043). When a partial correlation controlling for age was used to compare steps/day to body composition variables, negative correlations still existed for each variable. These correlations were significant for BMI (P<0.001), % body fat (P<0.001), waist circumference (P=0.002), and hip circumference (P=0.015). These results show that women who accumulated more steps/day had significantly lower body fat percentages, BMI values, waist circumferences, and hip circumferences.