REDUCTION IN CARDIOVASCULAR-DISEASE RISK-FACTORS - 6-MONTH RESULTS FROM PROJECT ACTIVE

Background. Project Active is a randomized clinical trial that compare s a lifestyle physical activity intervention with a traditional struct ured exercise intervention. The purpose of this paper is to report 6-m onth results of these interventions on cardiovascular disease (CVD) ri sk factors among healthy, sedentary, middle-aged men and women, and to examine the psychological strategies used in each group (Lifestyle an d Structured) to reach the level of physical activity recommended by t he Centers for Disease Control and Prevention (CDC) and American Colle ge of Sports Medicine (ACSM) and to achieve changes in these CVD risk factors. Methods. A total of 116 initially sedentary men (mean +/- SD self-reported physical activity, 33.2 +/- 1.4 kcal.kg(-1).day(-1)) and 119 women (32.9 +/- 1.0 kcal.kg(-1).day(-1)), ages 35-60 years (46.0 +/- 6.7 years) were randomly assigned to a 6-month lifestyle physical activity counseling intervention or a 6-month gymnasium-based structur ed program. At baseline and 6 months, changes in lipid and lipoprotein -cholesterol concentrations, blood pressure, and body composition and cognitive and behavioral measures of change were assessed. One-way ana lyses of variance with covariate adjustment were used to test for betw een-group differences in CVD risk factors. Associations between achiev ing the CDC/ACSM criterion and changes in cognitive and behavioral mea sures were assessed with multiple logistic regression models. Results. After 6 months of intervention, 78% of Lifestyle participants and 85% of Structured participants were meeting or exceeding the CDC/ACSM rec ommendation of accumulating 30 min or more of moderate-intensity physi cal activity on most, preferably all, days of the week. This was verif ied by a significant increase in cardiorespiratory fitness in both gro ups. The adjusted mean increase in maximal METs (VO2peak divided by 3. 5 ml.kg(-1).min(-1)) between treadmill tests was 0.4 kcal.kg(-1).hr(-1 ) (P < 0.001) for Lifestyle and 1.1 kcal.kg(-1).hr(-1) (P < 0.001) for Structured. There was a significant difference between intervention g roups for this outcome. Both groups had significant reductions in tota l cholesterol, total cholesterol/HDL-C ratio, diastolic blood pressure , and percentage of body fat. There were no significant between-group differences in changes in these outcomes. Adjusted mean changes in tot al cholesterol, systolic blood pressure, and percentage of body fat in Lifestyle [in Structured] participants were -0.2 [-0.3] mmol.L-1, -3. 2[-1.8] mm Hg, and -1.4 [-1.7] %, respectively. There were significant associations between achieving the CDC/ACSM physical activity criteri on and greater use of the cognitive and behavioral strategies of chang e. Both groups changed self-efficacy and many of the behavioral measur es, but there were no significant differences between intervention gro ups. Conclusions. These results demonstrate that lifestyle physical ac tivity counseling is as effective as structured exercise programs in i ncreasing physical activity and improving CVD risk factors after 6 mon ths among initially sedentary men and women. Furthermore, specific cog nitive and behavioral counseling strategies were increased significant ly as a result of the intervention. These strategies are effective and could be used in a wide variety of settings. (C) 1997 Academic Press.