Basal Metabolic Rate (BMR) is the total number of calories that the body requires to perform its most basic, life-sustaining functions while at complete rest. These functions include breathing, circulating blood, controlling body temperature, cell growth, and brain and nerve function. BMR typically accounts for the largest portion (60-75%) of an individual's total daily energy expenditure. It is influenced by several factors, including age, sex, genetics, and body composition.
Because muscle tissue is more metabolically active than fat tissue, increasing lean muscle mass is one of the most effective ways to raise BMR. During a weight loss journey, it is common for the BMR to decrease as the body attempts to conserve energy—a process known as metabolic adaptation. Successful protocols incorporate strategies, such as adequate protein intake and resistance training, to preserve muscle mass and keep the BMR as high as possible to prevent weight regain.
The definitive guide by Russell Clark, FNP-C, APRN