Blood Lipid Changes after a 10-Week Unsupervised Worksite Physical Activity Program

Abstract

PURPOSE: Promoting physical activity is an important public health issue. Estimates suggest that 40 percent of adults do not engage in any leisure time physical activity. The worksite is an environment which may be conducive to promoting physical activity. The purpose of this study was to see whether a relatively unstructured approach to promoting physical activity and health at the worksite using pedometers and incentives would improve blood lipids. METHODS: All 72 employees of a small private corporation at three separate worksites were given the opportunity to take part in the 10-week intervention. Blood lipids of the 30 subjects who agreed to participate were measured before and after the intervention. Each subject was given a pedometer (New Lifestyles SW-200) and instructed on proper use, and weekly log sheets to track their daily step total. To encourage adherence each week subjects who turned in their weekly logs were rewarded with incentives. Each weekday subjects were also sent a daily e-mail health tip. The intervention also consisted of three 30-minute educational seminars. These seminars focused on the importance of physical activity, healthy nutrition, and stress management. RESULTS: Thirty subjects (24 females and 6 males) with a mean (+ SD) age of 44.53 + 9.74 years participated in the intervention. Paired samples t-tests showed that mean (+ SD) total cholesterol declined from 208.07 + 51.88 to 199.68 + 48.10 mg/dL (p<0.145); LDL-C declined significantly from 122.12 + 41.09 to 110.81 + 39.81 mg/dL (p<0.010); HDL-C increased significantly from 58.16 + 20.23 to 64.51 + 21.44 mg/dL (p<0.000); and as a consequence the ratio of TC:HDL-C declined from 4.17 + 3.31 to 3.20+ 1.04 (p<0.09).TG declined from 132.39+85.46 to 127.29 + 121.78 mg/dL (p<0.728). For the 10 weeks each subject averaged 5,134.8 + 3,287.9 steps per day. A significant correlation (r2 =0.414, p<0.028) existed between each subject's pre - post difference in HDL-C and the total number of steps completed. CONCLUSIONS: The results of this worksite intervention indicate that significant changes in lipid profiles may occur in adults with a relatively easy to implement and inexpensive short-term physical activity intervention.