The association among three aspects of physical fitness and metabolic syndrome in a Korean elderly population

Background: The purpose of current study is to evaluate the association between physical fitness level and the prevalence of metabolic syndrome (MS) in a Korean elderly population. Methods: A cross-sectional study measuring physical fitness and components of MS in a health promotion center of a general hospital for routine health check-ups. A total of 227 subjects >60 years old agreed to participate. A lifestyle questionnaire that included cigarette smoking, alcohol consumption, and physical activity was checked. Body weight, height, blood pressure, fasting glucose, total cholesterol, triglycerides, high density lipoprotein-cholesterol, low density lipoprotein-cholesterol, C-reactive protein, and glycated hemoglobin were measured. Muscular strength was assessed by measuring grasping power. Muscular endurance was evaluated using a sit-up test. Cardiopulmonary fitness was assessed via the Tecumseh step test (measuring hear rates at 1 min post-exercise). Results: The highest tertile muscular endurance group (sit-ups > 15 in men, > 10 in women) was 0.37 times less likely to have MS [95 % confidence interval (CI) 0.17-0.84; p = 0.036] compared to that in the lowest tertile group (< 11 in men, 0 in women), and the highest tertile in the cardiopulmonary fitness group (heart rate at rest > 91/min in men, > 92/min in women) was 2.81 times more likely to have MS (95 % CI 1.27-6.18; p = 0.038) compared to that in the lowest tertile group (< 81/min in men, < 80/min in women). Conclusions: Cardiopulmonary fitness and muscular endurance were related to MS in a Korean elderly population after adjusting for age, sex, current smoker, current alcohol drinking, and physical activity. Older adults should be encouraged to increase their cardiopulmonary fitness and muscular endurance.