The Effects of a Six-Week Weight Loss Program on Body Composition and Muscular Strength and Endurance

Introduction: The purpose of this study was to investigate body composition and muscular strength and endurance adaptations with a six-week weight loss program. Methods: Body fat, fat-free mass, waist and hip circumferences, resting metabolic rate, and muscular fitness were assessed before and after the six-week program in 40 middle-aged women.Results: There was a significant reduction in body fat (P < 0.001) and waist and hip circumferences (P < 0.01) while there was an increase in fat-free mass (P < 0.001). There was a significant improvement in muscular strength in all muscle groups examined (P < 0.01) and an improvement in muscular endurance in forearm plank hold and wall taps for time. Resting metabolic rate did not change after the six-week weight loss program.Conclusions: This weight loss program was effective in improving body composition while improving muscular strength and endurance. However, this combination of diet, exercise, and water consumption was not effective in changing resting metabolic rate. This study contributes to the necessity to create an exercise and diet program of optimal duration and intensity that is effective in altering body composition and improving muscular fitness while improving resting metabolic rate for the long-term maintenance of optimal body weight.