The atherosclerosis index during body weight reduction is improved with exercise

Abstract

Introduction

Body weight reduction is often used for addressing lifestyle-related diseases, and for slimming down or improving the competitiveness of athletes. It is known that high-density lipoprotein-cholesterol (HDL-C) levels can be increased by habitual exercise, while low-density lipoprotein-cholesterol (LDL-C) levels may not always be decreased by dietary restriction or exercise. We hypothesized that the levels of not only HDL-C, but also LDL-C improve more with body weight reduction by a combined diet-and-exercise regimen than that by a diet-only regimen.

Summary of facts and results

Six healthy young adult male volunteers participated in two 10-day crossover experiments (20 days total). The first 5 days comprised an adjustment period (energy intake, 2521 ± 304 kcal/day (mean ± standard deviation)). During the second 5-day period, participants either reduced their energy intake to 1261 ± 152 kcal/day, or reduced their energy intake to 1891 ± 228 kcal/day and exercised on a bicycle ergometer to consume 630 ± 76 kcal/day. Decreases in the serum total cholesterol (TC), LDL-C, and apolipoprotein (apo) B levels were significantly larger, and decreases in the HDL-C and apo A1 levels were significantly smaller with the diet-and-exercise regimen than with the diet-only regimen. Consequently, the atherosclerosis index (AI: (TC–HDL-C)/HDL-C ratio) was significantly lower, and the degree of its reduction was significantly larger, after the diet-and-exercise regimen than after the diet-only regimen.

Conclusion

These results suggest that reducing the body weight by a combination of diet and exercise has more beneficial effects on cholesterol metabolism, including changes in apo levels, than diet alone in healthy young adults.