Background: Obesity is a risk factor for obesity-related disorders such as type 2 diabetes mellitus. That obesity could hinder the individual work capacity and the cost for managing obesity complications. Aim of Work: was to study the effect of diet induced obesity and swimming on the plasma glucose, insulin, insulin resistance, body mass index (BMI), muscle mass and muscle glycogen, and fat tissue weight according to meal timing. Materials and Methods: Sixty Sprague dawely adult rats were randomized into two equal groups control group and obese group. The first was exposed for induction of obesity by hyper caloric diet and the other completes the standard one. At the end of the 12th week of age, rats started the exercise program for three months. The immediate group receives their meals immediately after exercise and the delayed one receive their meals three hours later. Then after receiving their meal, free access to food was allowed. Samples of blood were taken from all animals at the beginning and at the end of experiment and examined for plasma glucose and plasma insulin. Insulin resistance was estimated by HOMA-IR formula. Results: Immediate feeding after the exercise bout produced greater increase in muscle bulk and muscle glycogen, with decreased fat tissue weight in comparison with that of the corresponding delayed feeding either on obese and control groups Conclusion: Immediate meal timing was a powerful strategy to improve glucose homeostasis. Data of the present study showed that muscle bulk was greater with lower fat tissue weight in the immediate feeding group versus the delayed one.