High metabolism?

In general teens have a higher metabolism than older folks, since metabolism decreases with age but it really depends on a lot of factors. A teen who sits on their all day playing video games probably have a slower metabolism than a 30 year old who works out daily. Metabolism varies due to a lot of factors including, age, genetics, weight, diet and activity level. A very generalized way to determine your basal metabolic rate (the amount of calories you'd burn if you laid in bed all day) is to multiply your weight by 10. Multiply it buy 12 and you'll get how many calories you burn doing stuff like sitting in cl without doing any major exercise.