Objective: To study the influence of physical activity and certain dietary habits on cardiovascular risk factors in middle age men.
Design: Prospective cross sectional study.
Setting: Primary care.
Subjects: Healthy male workers participating in a preventive medical examination.
Interventions: All participants were subjected to a physical activity inquiry, dietary recall, inquiry about smoking habits and anthropometric assessment. Also, blood pressure was measured and a fasting blood sample was obtained to assess serum total and HDL cholesterol, triglycerides and blood glucose. Multiple stepwise and canonical regressions were used to analyze data.
Results: Four hundred eleven subjects aged 46.8 +/- 10 years old were studied. Twenty four percent smoked, mean body mass index was 26.2 +/- 2.6, mean calorie intake was 11.7 +/- 3 MJ/day and mean calorie expenditure 10.6 +/- 1.1 MJ/day or 1.52 +/- 0.13 times the resting metabolic rate. Physical activity, body mass index and fiber intake appeared as independent but weak predictors of total and LDL cholesterol. Alcohol intake, age and body mass index were predictors of HDL cholesterol and blood pressure was predicted by age, fiber intake and body mass index. Canonical analysis showed that 54% of blood pressure variation is explained by age, body mass index and fiber intake and that 31% of HDL cholesterol variation is explained by alcohol intake.
Conclusions: Physical activity has a weak influence on serum total and LDL cholesterol. Alcohol intake is the main predictor of HDL cholesterol in these workers.