Final answer:
Lean body mass includes muscles, bones, and organs, and it significantly influences the basal metabolic rate (BMR), thereby affecting calorie burn and weight regulation. Increased lean body mass leads to a higher BMR, which aids in weight control. Factors such as exercise, diet, age, gender, and genetics also impact an individual's lean body mass and metabolic rate.
Step-by-step explanation:
Lean body mass is the weight of everything in the body except for the fat. This includes muscles, bones, organs, and fluids. Having a greater proportion of lean body mass contributes to a higher basal metabolic rate (BMR), as lean tissue is more metabolically active than fat tissue. An increased BMR means that more calories are burned at rest, aiding in weight regulation.
Physical exercise influences lean body mass by building extra lean tissue. This process not only burns calories during the activity but also raises the BMR, allowing for more calorie burn even while sleeping. Moreover, factors like age, gender, and genetics also play significant roles in an individual's metabolism.
For instance, men generally have a higher BMR due to more lean muscle mass compared to women. As one ages, BMR tends to decrease; however, through the appropriate modifications in diet and exercise, lean body mass and metabolism rate can be increased.
Understanding the role of lean body mass in metabolism and weight regulation is crucial for effective dieting and maintaining a healthy body weight. Additionally, the metabolic rate adjusts to dietary changes over a period, which influences how effectively the body stores or metabolizes fat.