Cardiorespiratory Fitness and Metabolic Markers in Healthy Young Adult Men

[Purpose] The purpose of this study was to clarify the relationship between cardiorespiratory fitness and metabolic markers, including leptin, in healthy young adults. [Subjects] The subjects were 51 healthy young men (mean age, 21.6 years; range, 18-31 years). [Methods] Ventilatory threshold and maximal oxygen uptake were measured on a cycle ergometer. The metabolic markers, HDL-cholesterol, triglyceride, fasting glucose, fasting insulin and leptin, were also measured, as well as and body composition, body height, body weight, percentage fat mass, waist circumference, and hip circumference. Blood pressure levels were recorded at rest. [Results] Our results show that lower cardiorespiratory fitness was significantly associated with higher storage of fat, lipid markers of developing atherosclerosis, and circulating leptin levels. Higher circulating leptin levels were also associated with metabolic risk markers such as obesity and insulin resistance. [Conclusion] Our results suggest that appropriate cardiorespiratory fitness may improve circulating metabolic markers even in healthy young men. It is therefore important that all persons should have high cardiorespiratory fitness from an early period of life for the effective prevention of cardiovascular disease.