I┬┤m an 18 year old boy, I weigh 63 kg and I┬┤m 1,86 cm tall; and therefore i have a BMI of about 17. This is too low and I don┬┤t believe its healthy. So I┬┤ve been trying to gain mass through hyper-caloric diets, but it looks like my metabolic rate is too high. So the last option I┬┤ve thought of is gaining that weight through muscle, but I have no idea on the most efficient way to do it in terms of workout and diet. I┬┤ll gladly appreciate any help 😀
When it comes to gaining weight (especially lean mass) there is no difference between upper and/or lower body approach. At your age having high metabolism is not unusual. Since I know nothing else about you, the best advice I can give you is to seek the assistance of a trainer or a coach. I’m not sure in which country you are at, but visiting a local gym might be the best way to go about it and seek the guidance of a mentor or a professional trainer. Same goes with diet.