Final answer:
A higher percentage ofB) lean muscle increases the metabolic rate because lean muscle demands more energy, even at rest, than fat tissue. Exercise, including strength training, can increase lean muscle mass, thus boosting the basal metabolic rate (BMR).
Step-by-step explanation:
Having a higher percentage of lean muscle vs. fat can help your metabolic rate because lean muscle requires more energy, thus boosting the metabolic rate. This can be seen in the fact that lean tissue is more metabolically demanding than fat tissue. Metabolic rate at rest, known as the basal metabolic rate (BMR), is higher for those with lean muscle mass. In contrast, fat tissue does not require as much energy to maintain itself. Moreover, exercise not only burns calories but also helps raise the BMR by building extra lean tissue.
Muscle mass naturally declines with age, which can lead to a decrease in metabolic rate by as much as 5 percent per year. Furthermore, men tend to have a higher BMR than women, owing to typically having more lean muscle mass. However, regardless of gender, having more lean muscle mass will benefit your metabolic rate. Thus, engaging in regular exercise, including strength training, is essential to maintain or increase lean muscle mass and keep your metabolism active.