Factors that can affect a person’s basal metabolic rate (BMR) include age, gender, body composition, and genetics. As people age, BMR typically decreases due to losing muscle mass and hormonal changes. Gender also plays a role, as men usually have a higher BMR than women due to greater muscle mass. Additionally, individuals with higher muscle percentage burn more calories at rest compared to those with a higher body fat percentage. Other influencing factors may include physical activity levels, food intake, and environmental conditions, all of which can impact overall metabolism.