[Effect of intermittent versus continuous exercise on obesity and fatty liver in rats fed with high-fat diet]

To examine the effects of continuous and intermittent exercises on obesity and fatty liver in rats fed with high-fat diet.

Wistar rats were randomly assigned into routine diet (R) and high-fat diet (H) groups, and each group were subdivided into sedentary group (S), continuous exercise (CE) group, and intermittent exercise (IE) group (n=8). In the CE group, the rats were forced to swim continuously for 90 min once daily, and those in the IE group swam for 30 min for 3 times (at a 4-h interval) daily. Both the CE and IE groups exercised for 5 days a week for 8 consecutive weeks. After the experiment, the retroperitoneal, epididymal, and visceral white and brown adipose tissues, the liver, and the gastrocnemius muscle of the rats were weighed. The lipogenesis rate was determined by incorporation of (3)H(2)0 into saponified lipids, and the blood lipid profiles were analyzed. The body weight and food intake of the rats were recorded daily.

IE appeared to be more efficient than CE in reducing the adverse effects of high-fat diet and sedentarism. Compared with CE, IE resulted in an improved lipid profile with reduced food intake, body weight gain, visceral and central adiposity, and fatty liver. The effect of high-fat diet and different exercises on weight gain, adiposity, fatty liver, and lipid profile in rats was associated to the manner of exercise, time of each session, age, gender, and length of observation period.

Intermittent exercise is an important nonpharmacological strategy to control obesity and the related complications.